MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Invertebrate Biology' source. Thu, 09 Feb 2012 14:32:09 +0100 http://www.medworm.com/index.php?rid=5624573&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00256.x We examined blue streak variability in male crabs in response to physical factors (light and temperature) and social context to begin to understand what causes its dynamic response. The blue streak darkens in response to decreased ambient light, but does not respond to changes in temperature. In the field, it is brighter when crabs are roaming on the mudflat or fighting, but darker when crabs are basking or performing waving displays. The highly visual nature of fiddler crabs and the dynamic character of the blue streak suggest that it may communicate information about the state of a crab or its environment. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5624573 Thu, 01 Dec 2011 05:00:00 +0100 5624573 http://www.medworm.com/index.php?rid=5603781&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00255.x AbstractStandard metabolic rate (SMR) and resistance to body dehydration (BD) are important physiological traits that have an effect on water balance and the amount of energy available for activity and production, and thus could contribute to variation in life history traits expressed across a range of environments. Few studies have tested whether SMR and BD show consistent between‐individual variation in molluscs. Significant repeatability of SMR and BD indicates that the traits might be heritable and therefore a possible target for natural selection, so describing the repeatability of SMR and BD is important in studies of phenotypic variability. Here, we studied energy metabolism (body mass‐corrected SMR) and the change in the scaling relationship of SMR and body mass in response to ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5603781 Thu, 01 Dec 2011 05:00:00 +0100 5603781 http://www.medworm.com/index.php?rid=5576552&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00254.x AbstractThe shells of most anomalodesmatan bivalves are composed of an outer aragonitic layer of either granular or columnar prismatic microstructure, and an inner layer of nacre. The Thraciidae is one of the few anomalodesmatan families whose members lack nacreous layers. In particular, shells of members of the genus Thracia are exceptional in their possession of a very distinctive but previously unreported microstructure, which we term herein “dendritic prisms.” Dendritic prisms consist of slender fibers of aragonite which radiate perpendicular to, and which stack along, the axis of the prism. Here we used scanning and transmission electron microscopical investigation of the periostracum, mantle, and shells of three species of Thracia to reconstruct the mode of shell calcification an... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5576552 Thu, 01 Dec 2011 05:00:00 +0100 5576552 http://www.medworm.com/index.php?rid=5556703&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00253.x AbstractAtlantic bobtail squid (Sepiola atlantica) in northwest Spain show seasonal variation in population structure, with juvenile abundance peaking during summer and autumn. However, whether similar patterns exist for reproduction is unknown. Therefore, we describe the reproductive biology of 505 specimens of S. atlantica collected monthly during two consecutive years at two different sites off of Areamilla beach in the Ría de Vigo. Mature males displayed a type of sexual dimorphism previously unknown in members of this species, developing a muscular nodule in the base of each of the ventral arms over ontogeny. Reproductive output of both sexes was similar to that of other bobtail squids. Relative oocyte size (~10% mantle length) appeared to be similar to those of other bobtail squids.... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5556703 Thu, 01 Dec 2011 05:00:00 +0100 5556703 http://www.medworm.com/index.php?rid=5549617&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00252.x AbstractTo better understand the mating systems of majoid crabs, we studied the functional anatomy of the female reproductive systems of the spider crabs Leurocyclus tuberculosus and Libinia spinosa, comparing them with those of other Majoidea. Adult females were measured and dissected, and their reproductive systems described macroscopically and histologically. In females of both species, the seminal receptacles are paired globular structures of ecto‐mesodermal origin. The mesoderm‐derived region is lined by a stratified epithelium. The anchoring, proliferative, and secretory strata are clearly recognizable. The ectoderm‐derived region is lined by a simple cylindrical epithelium underlying a cuticle that increases in thickness toward the vagina. The transition between the ectoderm a... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5549617 Thu, 01 Dec 2011 05:00:00 +0100 5549617 http://www.medworm.com/index.php?rid=5512197&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00251.x This study confirmed that members of E. rosea are robust generalist predators, capable of successfully tracking native and non‐native snails, and should not be introduced as biologic control agents. These results may be useful to managers, as they provide insight into how trail following could be used to trap members of this invasive species. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5512197 Thu, 01 Dec 2011 05:00:00 +0100 5512197 http://www.medworm.com/index.php?rid=5473478&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00250.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5473478 Thu, 01 Dec 2011 05:00:00 +0100 5473478 http://www.medworm.com/index.php?rid=5473477&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00249.x We present four lines of evidence indicating rhogocytes in M. crenulata synthesize KLH1. First, at the transmission electron microscopy (TEM) level, dilated cisternae of RER containing material similar in size and shape to KLH were observed in rhogocytes examined throughout the year. Second, KLH1 mRNA was identified exclusively in tissue samples that contained rhogocytes; no mRNA for KLH1 was identified in samples containing only hemocytes. Third, immunoperoxidase staining with antibodies specific to KLH was localized only to rhogocytes. Fourth, in situ hybridization with a probe specific for M. crenulataKLH1 demonstrated KLH1‐specific mRNA was present only in rhogocytes. Identification of the cells responsible for the synthesis of KLH is important because of the clinical significance of... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5473477 Thu, 01 Dec 2011 05:00:00 +0100 5473477 http://www.medworm.com/index.php?rid=5374947&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00243.x We report on the distribution, movement patterns, and microhabitat preferences of E. rosea in a gulch in the Waianae Mountains, Oahu, Hawaii, because such data will help focus management actions at a local scale to protect native snail populations in areas where E. rosea is established. The Waianae Mountains harbor many endangered or threatened snails, most currently found in isolated habitat patches near the ridges. Conversely, most living individuals (28/29) and shells (46/56) of E. rosea were collected within the gulch, which supported higher densities of other native and non‐native snails, and was cooler and more moist than the ridges. Thirteen individuals of E. rosea were tracked (eight directly using a bobbin and thread method, and five indirectly by mark–recapture); most (10/13)... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5374947 Fri, 28 Oct 2011 04:00:00 +0100 5374947 http://www.medworm.com/index.php?rid=5374946&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00245.x AbstractThe dynamics and consequences of the varied reproductive modes of marine invertebrates is a rich and vibrant field of inquiry for ecological and evolutionary studies. One mode of reproduction that is not as well‐studied as others is “spermcasting” or “spermcast mating,” when males broadcast sperm and females retain eggs and brood developing embryonic stages. This type of reproduction occurs in two small (maximum adult shell length ~5–6 mm) venerid bivalves, Nutricola confusa and N. tantilla, that live in protected bays of the temperate eastern Pacific. Females of these species brood developing embryos in chambers formed by the inner demibranchs, and release fully formed juveniles. We discovered that upon exposing clams to fluvoxamine, a selective serotonin reuptake inh... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5374946 Thu, 01 Sep 2011 04:00:00 +0100 5374946 http://www.medworm.com/index.php?rid=5355191&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00244.x AbstractSymbiotic crustaceans are expected to live solitarily with their hosts when members of their host species are small (relative to symbiont body size) and structurally simple. We tested the hypothesis of a solitary lifestyle in Ascidonia flavomaculata, a symbiotic shrimp that inhabits the branchial chamber of the relatively small and structurally simple tunicate Ascidia mentula in the subtidal zone of the Islas Baleares, Spain. We found that members of A. flavomaculata dwell as solitary individuals in the branchial chamber of ascidians at a higher frequency than expected by chance alone. Given this host use pattern of A. flavomaculata, we hypothesized that males actively move among host individuals in search of receptive females. We provide several lines of evidence consistent with t... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5355191 Thu, 01 Sep 2011 04:00:00 +0100 5355191 http://www.medworm.com/index.php?rid=5321397&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00242.x In this study, we show that diverse nudibranchs all have a pattern of TPep‐like immunoreactivity similar to that of T. diomedea, with thin tracts of TPep‐like immunoreactive (TPep‐LIR) neurites projecting to the epithelial layer. We also show that members of two non‐nudibranch gastropod species have a pattern of TPep‐innervation similar to that of the nudibranchs. In addition, we characterized two pairs of motor neurons in adults of the nudibranch Armina californica that are possible homologues of the Pd5 and Pd6 cells in T. diomedea. Activity in one of these pairs, the Pedal Peptidergic Dorsal 1 (PPD1) cells, was correlated with mucociliary locomotion. The second pair, the Pedal Peptidergic Ventral 1 cells, shared synchronous synaptic input with the PPD1 cells, a pattern consist... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5321397 Thu, 01 Sep 2011 04:00:00 +0100 5321397 http://www.medworm.com/index.php?rid=5310583&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00242.x In this study, we show that diverse nudibranchs all have a pattern of TPep‐like immunoreactivity similar to that of T. diomedea, with thin tracts of TPep‐like immunoreactive (TPep‐LIR) neurites projecting to the epithelial layer. We also show that members of two non‐nudibranch gastropod species have a pattern of TPep‐innervation similar to that of the nudibranchs. In addition, we characterized two pairs of motor neurons in adults of the nudibranch Armina californica that are possible homologues of the Pd5 and Pd6 cells in T. diomedea. Activity in one of these pairs, the Pedal Peptidergic Dorsal 1 (PPD1) cells, was correlated with mucociliary locomotion. The second pair, the Pedal Peptidergic Ventral 1 cells, shared synchronous synaptic input with the PPD1 cells, a pattern consist... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5310583 Thu, 01 Sep 2011 04:00:00 +0100 5310583 http://www.medworm.com/index.php?rid=5246080&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00240.x This study suggests that males are willing to suffer a decrease in sperm number if a mating opportunity occurs before the completion of sperm production. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5246080 Thu, 01 Sep 2011 04:00:00 +0100 5246080 http://www.medworm.com/index.php?rid=5233172&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00241.x AbstractThe sea anemone Anthopleura elegantissima is a common member of intertidal communities along the west coast of North America, and can experience extended periods of increased temperature during summertime low tides. Internal body temperatures of emersed individuals of A. elegantissima were monitored in a laboratory wind tunnel and in the field, and factors influencing the anemones’ thermal experience were examined. Larger body size and aggregation with conspecifics slowed body temperature increases in controlled wind tunnel conditions. In the field, anemones in the interior of an aggregation stayed cooler than those on the edges, and microhabitat features related to light exposure and surface orientation overshadowed any direct effects of body size. In the warmest month only (Jul... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5233172 Thu, 01 Sep 2011 04:00:00 +0100 5233172 http://www.medworm.com/index.php?rid=5155436&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00236.x We examined the presence and location of small cardioactive peptide (SCP)‐like neuropeptides in both the central and peripheral nervous systems of D‐hinge, newly eyed, and pediveliger larvae of Crassostrea virginica. Results indicate that SCP‐like substances are present early in development (D‐hinge larvae), and that presence in the central and peripheral nervous systems increases as the larva develops toward metamorphic competence (pediveliger larvae). In addition, in newly eyed and pediveliger larvae, SCP‐like labeling is found in a varying number of neurons within all central ganglia, with the possible exception of the accessory ganglia. Varicose labeling of axons is also documented within the ganglia, commissures, and connectives, as well as in peripheral nerves. Peripheral t... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5155436 Tue, 23 Aug 2011 23:00:00 +0100 5155436 http://www.medworm.com/index.php?rid=5155435&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00237.x In this study, I observed the behavior of a living colony of Conescharellina catella collected from the East China Sea and maintained in the laboratory for 2 months. The colony lived apex down, suspended above the substratum by several rhizoids arising in the apical two‐fifths of the colony, to a total height of nearly five times colony height. Starting from an uprooted position lying on the substratum, the colony reattached and righted itself to the erect position using existing or newly produced rhizoids. After I removed all rhizoids, the colony was able to right itself only after it regenerated rhizoids. In each of several series of observations, righting behavior involved similar steps and followed a similar time course, and it can thus be considered a stereotypical behavior. Histol... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5155435 Tue, 23 Aug 2011 23:00:00 +0100 5155435 http://www.medworm.com/index.php?rid=5155434&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00238.x AbstractThe genome of the non‐blood‐feeding glossiphoniid leech Helobdella robusta was screened for leech antiplatelet protein (LAPP), an anticoagulant that specifically inhibits collagen‐stimulated platelet aggregation. Previously identified LAPP sequences from Haementeria officinalis were used as queries against the predicted genes in the genome, employing a variety of BLAST protocols. Matches were reciprocally BLASTed against GenBank databases as a cross‐validation of the predicted annotations of the genes. A total of eight loci, positioned as a tandem array, were recovered with significantly low e‐values; these showed high sequence similarity (32.49% average sequence similarity of shared amino acid positions) to the known anticoagulants. Moreover, six of these possessed a pre... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5155434 Tue, 23 Aug 2011 23:00:00 +0100 5155434 http://www.medworm.com/index.php?rid=5116942&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00234.x Abstract. The polychaete Dipolydora commensalis is an obligate symbiont of hermit crabs and produces a burrow along the columella of the gastropod shells they inhabit. Adults of D. commensalis have short palps that they use to feed on particles dropped or brought in by the respiratory currents of hosts. To determine whether hermit crabs influence palp length, specimens of D. commensalis were isolated in glass capillary tubes and the growth of palps was measured over a 3‐week period. Palp length was also measured in worms isolated in gastropod shells with or without hermit crabs for 2 weeks. In addition, to determine whether adults of D. commensalis have regeneration capabilities like those of free‐living relatives, worms were cut at the fifth or 15th setiger and then monitored for 35�... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5116942 Sun, 07 Aug 2011 23:00:00 +0100 5116942 http://www.medworm.com/index.php?rid=5173843&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00235.x This study provides a detailed description of central and peripheral components of the larval nervous system in the Eastern oyster, Crassostrea virginica. Larvae at the D‐hinge, newly eyed and pediveliger stages were examined at the light level by means of serial histological section sets. D‐hinge larvae were found to have limited neurogenesis with only an anterior gangliar rudiment being present. As development progressed to the newly eyed larval stage, a single apical ganglion and paired cerebro‐pleural, pedal, and visceral ganglia were identified, forming a typical bivalve central nervous system loop. The nervous system of pediveligers was similar to that of newly eyed larvae, but added an additional accessory ganglion on the left and right sides, posterior to each gill rudiment. ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5173843 Tue, 31 May 2011 23:00:00 +0100 5173843 http://www.medworm.com/index.php?rid=5155433&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00239.x AbstractThe periodicity of sexual elements and soft tissue modifications during the life cycle of the hypercalcified sponge Petrobiona massiliana was investigated monthly from June 2006 to November 2007. Sexual reproduction, likely regulated by seawater temperatures, occurred during more than half of the year (from early April to late October); 70% of the samples appeared reproductively active. Specimens of P. massiliana displayed a high plasticity of tissue organization, allowing modulation and rearrangement of their aquiferous systems in response to life cycle phases and environmental changes. Permanent changes were observed in the basal region of the choanosome in non‐reproductive specimens, such as disorganization/restructuring events leading to remodeling of the aquiferous system. P... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5155433 Tue, 31 May 2011 23:00:00 +0100 5155433 http://www.medworm.com/index.php?rid=5116941&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00233.x Abstract. Black corals (Cnidaria: Antipatharia) are ecologically important members of the sessile invertebrate fauna, but due to their typical deep‐water environments (>50 m), very little is known about their basic biology, including reproduction. We used histological techniques to examine the sexual reproduction of members of eight species of antipatharians collected from the Hawaiian Islands over a wide depth range (10–1327 m). Gametes of all species examined were found in association with the primary transverse mesenteries, which in some cases reached into the cavity of lateral tentacles. Specimens contained either spermatocysts or oocytes, but never both within the same individual, suggesting either a gonochoric or a sequentially hermaphroditic mode of reproduction. No devel... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=5116941 Tue, 31 May 2011 23:00:00 +0100 5116941 http://www.medworm.com/index.php?rid=4974544&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00230.x Abstract. Workers of Crematogaster inflata possess the largest metapleural glands (relative to body size) known among ants, with reservoirs extending anteriorly up to the junction between the pro‐ and the mesothorax, and with over 1400 secretory cells on both sides together. This large secretory capacity is related to the gland's defensive function, which, in members of this species, is directed against larger arthropod and vertebrate enemies, and apparently not against microorganisms, in contrast to other ants, where the gland produces antibiotics. The gland is not equipped with any direct musculature. Secretion release is probably caused by contraction of the oblique longitudinal thorax muscles or by passive expulsion caused by external pressure. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4974544 Tue, 31 May 2011 23:00:00 +0100 4974544 http://www.medworm.com/index.php?rid=4779626&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00228.x Abstract. Here we report on the first quantitative survey of morphological variation in the sea urchin Heliocidaris erythrogramma within Western Australia and distinguish between two subspecies found to co‐occur in this region. We surveyed urchins at multiple spatial scales along the Western Australian coastline to assess variation in dermis and spine color and, using landmark‐based geometric morphometrics, spine morphology. Both color and morphology proved to be useful for separating subspecies within Western Australia. There were four major color morphs: red dermis/violet spines (56%), red/violet‐green (23%), red/green (7%), and white/green (10%). Members of the first two color morphs had bulbous spines with wide, flattened tips, a morphology that is unique to Western Australia and... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4779626 Mon, 02 May 2011 23:00:00 +0100 4779626 http://www.medworm.com/index.php?rid=4811855&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00231.x Abstract. Pachechinus bajulus is an endemic Australian sea urchin with an unusual mode of brooded larval development. We used mitochondrial and nuclear gene sequences to estimate the phylogenetic relationships among Pachechinus and other Echinometridae, including well‐studied species of Heliocidaris with planktonic development. We found strong evidence for the planktotrophic species Heliocidaris tuberculata as the sister group to a clade of three closely related species in which development is known (Heliocidaris erythrogramma, P. bajulus) or suspected (Pachechinus australiae) to be lecithotrophic. Clade support values and likelihood ratio tests rejected monophyly of Heliocidaris species. The sister group to H. erythrogramma is most likely the two Pachechinus species. We resolve the para... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4811855 Tue, 01 Mar 2011 00:00:00 +0100 4811855 http://www.medworm.com/index.php?rid=4794152&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00227.x Abstract. Because of their reproductive biology, spiders are extremely promising subjects for testing hypotheses on sexual selection. Further, their genital morphology provides useful characteristics for taxonomy. However, the structure and functional morphology of the genitalia of members of most spider groups are poorly known. This is especially true for members of the Haplogynae. In this article, the female genitalia of three oonopid species are described, using light and scanning electron microscopy. The male palps are also briefly described. The female genitalia of all these three species do not correspond to the description of haplogyne genital systems given in the literature. Receptacula are lacking in the genitalia of Opopaea deserticola and Zyngoonops sp. Sperm are present in the ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4794152 Tue, 01 Mar 2011 00:00:00 +0100 4794152 http://www.medworm.com/index.php?rid=4788039&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00232.x Abstract. Cues released by predators and injured prey often induce shifts in prey behavior that allow prey to evade predators, but also affect prey resource use. I investigated the effects of chemical and mechanical signals produced by injured snails (Physella gyrina) and predatory crayfish (Procambarus clarkii) on microdistributions of P. gyrina. In an initial experiment, I observed snail responses to the presence of a caged crayfish predator, to injured conspecifics, or to both. There were significant effects of time and the treatment × time interaction on the proportion of snails moving above the water line, with greater proportions of snails above the water line at night than during the day and with weak snail crawl‐out behavior being elicited by caged crayfish at night, but not dur... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4788039 Tue, 01 Mar 2011 00:00:00 +0100 4788039 http://www.medworm.com/index.php?rid=4779625&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00229.x Abstract. Although the reproductive biology and early life‐history stages of deep‐sea corals are poorly understood, such data are crucial for their conservation and management. Here, we describe the timing of larval release, planula behavior, metamorphosis, settlement, and early juvenile growth of two species of deep‐sea soft corals from the northwest Atlantic. Live colonies of Gersemia fruticosa maintained under flow‐through laboratory conditions released 79 planulae (1.5–2.5 mm long) between April and early June 2007. Peak planulation in G. fruticosa coincided with peaks in the chlorophyll concentration and deposition rates of planktic matter. Metamorphosis and settlement occurred 3–70 d post‐release. The eight primary mesenteries typically appeared within 24 h, and p... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4779625 Tue, 01 Mar 2011 00:00:00 +0100 4779625 http://www.medworm.com/index.php?rid=4774725&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00226.x Abstract. A retractable head region somewhat resembling the introvert of sipunculans is a characteristic feature of members of the annelid taxon Fauveliopsidae. The morphology of fauvelopsids is not well known, and additional data might help to resolve their relationships with other annelids and sipunculans. Ultrastructural investigations of the anterior end of adults of Fauveliopsis cf. adriatica revealed peculiar brain and sensory structures. From the neuropil of the brain, two pairs of lobes mainly composed of neuronal somata extend posteriorly into the peristomium and the following segment. The nuchal organs are embedded in the median pair of lobes, as are additional photoreceptor‐like sensory structures, the ocellar tubes, which are found at the bases of epidermal follicles that ext... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4774725 Tue, 01 Mar 2011 00:00:00 +0100 4774725 http://www.medworm.com/index.php?rid=4569974&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00225.x Abstract. The endemic Hawaiian gastropod Smaragdia bryanae is a specialized marine herbivore that uses the endemic seagrass Halophila hawaiiana as both food and habitat. These small neritids, their grazing scars, and their egg capsules are found year‐round on seagrass leaves, where they feed on protoplast contents released as the sharp outer‐lateral teeth of the snail's radula puncture leaf epidermal cells; the contents of these cells are likely swept into the mouth by the long, wispy cusps of the marginal teeth. Structural differences from the typical neritid radula include elongated outer‐lateral teeth with two sharply pointed cusps, delicate marginal teeth reduced in both size and number, and a compressed central section. Snails grazed on leaves of H. hawaiiana steadily in laborat... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4569974 Tue, 01 Mar 2011 00:00:00 +0100 4569974 http://www.medworm.com/index.php?rid=4565157&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00224.x Abstract. Autotomy of the elytra (scales) in the annelid Alentia gelatinosa occurs at a breakage plane near the junction between the elytron and its elytrophore (stalk), and requires fracture of the external epidermal cuticle. The mechanism of cuticular fracture was investigated by light and electron microscopy, glycoconjugate histochemistry, direct observation of autotomy in isolated preparations, and mechanical tests. The breakage plane crosses the elytrophoral wall at a cuticular thickening and passes through the subelytral cavity between the elytron and the terminal septum of the elytrophore. At the cuticular breakage zone (CBZ), the collagenous framework of the normal cuticle is replaced with non‐collagenous microfibrils. The CBZ has a complex glycoconjugate composition and includes... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4565157 Tue, 01 Mar 2011 00:00:00 +0100 4565157 http://www.medworm.com/index.php?rid=4438791&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00218.x In this study, we describe the reproductive strategy of the bivalve Gaimardia bahamondei to explore the possible causes of the association between semelparity and internal brooding. Males of this species exhibit continuous gonadal activity throughout the breeding season. Apparently continuous spawning of sperm is associated with an abundance of captured sperm in the adfrontal region of the gill filaments of both males and females. Females are capable of brooding three cohorts of embryos simultaneously while also producing three new cohorts of oocytes. This suggests that females are able to generate at least six cohorts of embryos during the breeding season. Embryos are brooded in the suprabranchial chamber and are individually surrounded by a membrane with a projecting peduncle; embryos ar... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4438791 Sat, 05 Feb 2011 00:00:00 +0100 4438791 http://www.medworm.com/index.php?rid=4481907&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00222.x Abstract. The effects of spatial competition among colonial marine organisms are often evident in the contact zones between colonies. These effects are especially pronounced when the interaction results in overgrowth or necrosis of one of the competitors. Ascidians, one of the dominant taxonomic groups in subtidal sessile communities, have specialized morula cells that provide a defense against microbial infections. Injuries resulting from interspecific competitive interactions might also act as a stimulus for this defensive mechanism. Therefore, we expected to see the recruitment of morula cells in tissues near competitor contact zones. To test the hypothesis that spatial competition elicits this immune response, we placed colonies of the ascidian Didemnum perlucidum from southeastern Bra... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4481907 Wed, 01 Dec 2010 00:00:00 +0100 4481907 http://www.medworm.com/index.php?rid=4463931&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00223.x Abstract. Blue crabs (Callinectes sapidus) prey on hooked mussels (Ischadium recurvum) growing epizoically on oyster clumps in estuaries along the Louisiana coast. In prey size‐selection experiments, blue crabs preferred small mussels (<30‐mm shell length) to larger mussels, possibly because handling time increased with mussel size. When crabs were given a choice of solitary mussels versus mussels in clumps on oysters in the laboratory, mortality was lower by 86% in clumped mussels. However, no size selection by crabs occurred with mussels in clumps, likely because smaller mussels escaped predation in crevices between larger mussels or oysters. When individuals of two size classes of mussels were exposed to water containing the scent of crabs and of mussels consumed by blue crabs, a... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4463931 Wed, 01 Dec 2010 00:00:00 +0100 4463931 http://www.medworm.com/index.php?rid=4445128&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2011.00221.x Abstract. A paucity of data on the reproductive cycle of crabs in the family Lithodidae inhibits both the development of management strategies and the formulation of hypotheses regarding the evolution of lithodid life histories. Life‐history parameters of Lopholithodes foraminatus from British Columbia, Canada, were investigated based on 26 females maintained in the laboratory and supplementary observations on other living and preserved animals. The rate of embryonic development was determined by measuring the percentage area occupied by yolk in lateral views of eggs removed from brooding females throughout development. Females of L. foraminatus exhibited biennial reproduction including an 18‐month brooding period. Females molted, mated, and extruded eggs in mid‐summer, and did not r... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4445128 Wed, 01 Dec 2010 00:00:00 +0100 4445128 http://www.medworm.com/index.php?rid=4438790&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00220.x Abstract. Intraspecific variation in eye size in relation to ecological factors has not been well studied. Here, for the first time, we show that larger eyes in a freshwater crustacean may be associated with the presence of predators. In central Pennsylvania (USA), individuals of the amphipod crustacean Gammarus minus have significantly larger eyes in two freshwater springs with numerous fish predators (Cottus cognatus) than in three springs with few or no fish predators. Although we do not know the precise causes of these differences, this study and previous work on cave populations of G. minus suggest that eye size is an evolutionarily malleable trait that may respond to multiple selection pressures, either directly or indirectly. Three plausible explanations for the eye‐size variation... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4438790 Wed, 01 Dec 2010 00:00:00 +0100 4438790 http://www.medworm.com/index.php?rid=4418430&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00219.x Abstract. Cnidarians have extracellular matrix, or mesoglea, situated between an outer epidermis and an inner gastrodermis. In this article, we describe the ultrastructure of the mesoglea of polyps of Nematostella vectensis during development and regeneration. The column wall of recently metamorphosed polyps had basal laminae composed of a meshwork of thin filaments underlying each epithelium and a network of unstriated thick (20–25 nm in diameter) and thin fibrils (∼5 nm) decorated with particulate matter. In juvenile polyps with eight tentacles, the system of thick fibrils was concentrated near the gastrodermis. In the column wall and mesenteries of the adult there were bundles of thick fibrils that ran parallel to the myonemes. In regenerating polyps 2 days after transection, th... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4418430 Wed, 01 Dec 2010 00:00:00 +0100 4418430 http://www.medworm.com/index.php?rid=4336949&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00216.x Abstract. Clionaids are excavating sponges, which live in and grow into calcareous substrates. We studied the sexual reproductive cycles of two clionaid sponges coexisting in a Mediterranean coastal basin (Porto Cesareo, Italy), Cliona viridis and Cliona celata, by analyzing monthly tissue samples of ten specimens of each species collected over a 2‐year period. From May to June of the second study year, supplementary samples were taken weekly. Up to 90% of the specimens of C. viridis and 70% of those of C. celata sampled were reproductive during the study. In both species, but particularly in C. viridis, reproductive investment, measured as the percentage of sponge tissue occupied by gametes, was high. Oocytes were present almost year‐round in both species, except for a 1–4‐month p... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4336949 Wed, 01 Dec 2010 00:00:00 +0100 4336949 http://www.medworm.com/index.php?rid=4317786&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00217.x Abstract. According to anecdotal evidence, some spiders are inaccurate mimics of ants, that is, they resemble one or several ant models in coloration, but not in body form. Here, we studied the mimetic accuracy of individuals of three myrmecomorphic species, Liophrurillus flavitarsis, Phrurolithus festivus, and Micaria sociabilis, and their association with ant models to find evidence in support of hypotheses suggested to explain the maintenance of inaccurate mimicry. We found that all three species occur together with their models. Individuals of L. flavitarsis and P. festivus associated with a few ant species, while specimens of M. sociabilis only associated with a single species. The density of spiders was several hundred times lower than that of their models. The myrmecomorphs resemble... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4317786 Wed, 01 Dec 2010 00:00:00 +0100 4317786 http://www.medworm.com/index.php?rid=4298276&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00215.x This study was focused on flatworm community structure in three protected areas located on the eastern border of the Araucaria Plateau in south Brazil. We addressed three main questions: (1) How species‐rich are Araucaria forests? (2) Are there any differences in the community structure within the three areas? (3) What is the distribution pattern of land flatworms in this type of forest? A total of 51 flatworm species in ten genera and two subfamilies were found. Non‐metric multidimensional scaling analysis showed that the assemblage structure differed within the three areas. The abundance and richness varied in time, being affected by an interaction between season and areas. Araucaria forests on the eastern border of the Araucaria Plateau should be considered a hotspot of land planari... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4298276 Wed, 01 Dec 2010 00:00:00 +0100 4298276 http://www.medworm.com/index.php?rid=4186547&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00214.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4186547 Sat, 20 Nov 2010 17:49:53 +0100 4186547 http://www.medworm.com/index.php?rid=4011397&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00209.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4011397 Tue, 31 Aug 2010 23:00:00 +0100 4011397 http://www.medworm.com/index.php?rid=4011396&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00210.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4011396 Tue, 31 Aug 2010 23:00:00 +0100 4011396 http://www.medworm.com/index.php?rid=3968510&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00207.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3968510 Tue, 31 Aug 2010 23:00:00 +0100 3968510 http://www.medworm.com/index.php?rid=4138449&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00213.x Abstract. The morphology of marine invertebrate larvae is strongly correlated with egg size and larval feeding mode. Planktotrophic larvae typically have suites of morphological traits that support a planktonic, feeding life style, while lecithotrophic larvae often have larger, yolkier bodies, and in some cases, a reduced expression of larval traits. Poecilogonous species provide interesting cases for the analysis of early morphogenesis, as two morphs of larvae are produced by a single species. We compared morphogenesis in planktotrophic and lecithotrophic morphs of the poecilogonous annelid Streblospio benedicti from the trochophore stage through metamorphosis, using observations of individuals that were observed alive, with scanning electron microscopy, or in serial sections. Offspring o... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4138449 Sun, 01 Aug 2010 00:00:00 +0100 4138449 http://www.medworm.com/index.php?rid=4095876&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00212.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4095876 Sat, 31 Jul 2010 23:00:00 +0100 4095876 http://www.medworm.com/index.php?rid=4011395&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00211.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=4011395 Sat, 31 Jul 2010 23:00:00 +0100 4011395 http://www.medworm.com/index.php?rid=3968509&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00208.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3968509 Sat, 31 Jul 2010 23:00:00 +0100 3968509 http://www.medworm.com/index.php?rid=3919972&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00206.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3919972 Sat, 31 Jul 2010 23:00:00 +0100 3919972 http://www.medworm.com/index.php?rid=3861377&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00203.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3861377 Sat, 31 Jul 2010 23:00:00 +0100 3861377 http://www.medworm.com/index.php?rid=3746282&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00202.x Abstract. The atrochid rotifer, Acyclus inquietus, is a sedentary predator that lives within the colonies of its prey, the rotifer Sinantherina socialis. After larvae infiltrate and become associated with the colony, they secrete a permanent gelatinous tube and undergo metamorphosis to the adult stage. We followed settlement and metamorphosis using bright-field microscopy to document specific larval behaviors after eclosion, and used epifluorescence and confocal microscopy of phalloidin-labeled specimens to visualize some of the morphological changes that occur during metamorphosis. Upon eclosion, larvae possess paired eyespots and a ciliated corona that functions strictly in locomotion. After leaving the parent's gelatinous tube, larvae eventually settle on unoccupied colonies of S. socia... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3746282 Mon, 12 Jul 2010 23:00:00 +0100 3746282 http://www.medworm.com/index.php?rid=3588535&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00201.x We examined the nuchal organs of adults of the nereidid polychaete Platynereis dumerilii by means of scanning and transmission electron microscopy. The most prominent features of the nuchal organs are paired ciliary bands located dorsolaterally at the posterior margin of the prostomium. They are composed of primary sensory cells and multiciliated supporting cells, both covered by a thin cuticle. The supporting cells have motile cilia that penetrate the cuticle and are responsible for the movement of water. Subapically, they have a narrowed neck region; the spaces between the neck regions of these supporting cells comprise the olfactory chamber. The dendrites of the sensory cells give rise to a single modified cilium that crosses the olfactory chamber; numerous thin microvillus-like process... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3588535 Fri, 21 May 2010 23:00:00 +0100 3588535 http://www.medworm.com/index.php?rid=3588536&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00200.x Abstract. The sexual system of the semi-terrestrial shrimp Merguia rhizophorae is described, along with natural history observations on this unusual caridean. Individuals of M. rhizophorae in the Bocas del Toro Archipelago, Panama, were found occupying fossilized coral terraces in the upper and mid-intertidal zones, inhabiting caves and crevices, in and out of water. These fossilized coral terraces represent a new habitat for this species, which was previously reported only from mangrove swamps. Males, which made up 65% of the studied population, were smaller than females on average. No small juvenile females were observed, but transitional individuals having the characteristics of both males (gonopores) and females (ovaries) were observed in the population. These data suggest that individ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3588536 Thu, 20 May 2010 23:00:00 +0100 3588536 http://www.medworm.com/index.php?rid=3871827&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00205.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3871827 Fri, 30 Apr 2010 23:00:00 +0100 3871827 http://www.medworm.com/index.php?rid=3861376&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00204.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3861376 Fri, 30 Apr 2010 23:00:00 +0100 3861376 http://www.medworm.com/index.php?rid=3841819&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00186.x Abstract. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3841819 Fri, 30 Apr 2010 23:00:00 +0100 3841819 http://www.medworm.com/index.php?rid=3841817&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00200.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3841817 Fri, 30 Apr 2010 23:00:00 +0100 3841817 http://www.medworm.com/index.php?rid=3501179&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00199.x Abstract. We compared responses of adults and larvae of the brooding corals Pocillopora damicornis and Seriatopora hystrix to 12-h exposures to constant temperature treatments (21°C, 28°C, or 30°C) and a treatment in which temperature fluctuated from 28° to 21°C, simulating daily temperature variation generated by tidally driven upwelling in their natural habitat (Nanwan Bay, southern Taiwan). In all treatments, the maximum dark-adapted quantum yield of photosystem II (FV/FM) of the larvae was [sim]49% lower than that of adult corals; FV/FM in the larvae also differed among temperature treatments, with the highest values in the fluctuating treatment. These results show that the larvae of at least P. damicornis are more sensitive to temperature than adults, and suggest that larvae are ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3501179 Fri, 23 Apr 2010 23:00:00 +0100 3501179 http://www.medworm.com/index.php?rid=3448162&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00198.x This study explores the relationships among these groups using a combined analysis with seven molecular loci (18S rRNA, 28S rRNA, histone H3, 16S rRNA, cytochrome c oxidase subunit I [COI], myosin heavy-chain type II, and elongation factor-1[alpha] [EF-1[alpha]]) sequenced for 31 ingroup taxa and eight outgroup taxa. The deep evolutionary splits among these groups have made resolution of stable relationships difficult, and so EF-1[alpha] and myosin are used in an attempt to re-examine these ancient radiation events. Three phylogenetic analyses were performed utilizing all seven genes: a single-step direct optimization analysis using parsimony, and two-step approaches using parsimony and maximum likelihood. A single-step direct optimization parsimony analysis was also performed using only f... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3448162 Wed, 07 Apr 2010 23:00:00 +0100 3448162 http://www.medworm.com/index.php?rid=3440299&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00197.x Abstract. The ultrastructure of the male reproductive system in the polyclad flatworm Pleioplana atomata is described. Numerous testes are scattered throughout the entire body but are heavily concentrated on the ventral side. All stages of differentiating sperm cells are present in all testes follicles. Intercellular bridges connect spermatocytes and spermatids derived from a single spermatogonium. In the distal part of spermatids, a zone of differentiation develops with a row of microtubules beneath the plasmalemma. Adjacent to these microtubules, an intercentriolar body is flanked by two basal bodies that give rise to two axonemes (each with a 9+"1" microtubular pattern) that face in opposite directions. The Golgi complex appears in the central portion of the spermatid and produces numer... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3440299 Mon, 05 Apr 2010 23:00:00 +0100 3440299 http://www.medworm.com/index.php?rid=3440300&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00196.x Abstract. Previous studies suggest that phototaxis in sponge larvae is generated by the bending of a tuft of long posterior cilia (LPC). The photoresponsiveness of these cilia is often assayed by examining their reaction to sudden changes in light intensity. Here, we document and describe the larvae of the tropical marine sponges Neopetrosia proxima and Xestospongia bocatorensis and examine the phototactic behavior of their larvae. Both species brood ovoid, tufted parenchymella larvae, clearly countering an earlier hypothesis that all petrosid sponges are oviparous. Larvae of N. proxima were positively phototactic and settled after 2 d, while larvae of X. bocatorensis were negatively phototactic and settled in as little as 4 h. In both species, LPC quickly responded to changes in the light... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3440300 Sun, 04 Apr 2010 23:00:00 +0100 3440300 http://www.medworm.com/index.php?rid=3841818&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00198.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3841818 Wed, 31 Mar 2010 23:00:00 +0100 3841818 http://www.medworm.com/index.php?rid=3345904&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00195.x Abstract. The topic of tissue and organ regeneration has been of interest to life scientists ever since the phenomenon was noticed. The reason for this is obvious: if one can learn what drives and controls regeneration, i.e., how lost or damaged structures can be replaced, one not only has a better chance to understand an animal's embryogenesis and evolutionary relationship with other taxa, but one would also be in a better position to treat organ loss or tissue damage in humans. In this context, the possible restitution of individual sensory neurons or nerve projections has been of special interest to us. We identified central visual projections in several gastropod species and found that: (1) projections are very extensive across the brain and (2) they have connections with other systems... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3345904 Tue, 09 Mar 2010 00:00:00 +0100 3345904 http://www.medworm.com/index.php?rid=3334635&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00194.x In this study, 180 paralarvae of D. gigas were collected off the west coast of the Baja California peninsula and identified by sequencing a 369-bp fragment of the cytochrome oxidase I gene. Of these, 77 specimens, 0.8[ndash]6.0 mm in mantle length, were described. Indices based on morphometric ratios were used to determine whether the shapes of different body structures were reliable for identifying the paralarvae. For two ratios, the results appear to discriminate members of D. gigas from those of S. oualaniensis. Additionally, eye or intestinal photophores were not observed in any paralarvae of D. gigas. Morphological and morphometric information provided a valuable basis for the discrimination and identification of these two species. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3334635 Fri, 05 Mar 2010 00:00:00 +0100 3334635 http://www.medworm.com/index.php?rid=3330746&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00184.x In this study, the associated fauna from a variety of sponges and one species of tunicate collected by submersible from the continental shelf and slope of the southeastern United States at depths in the range 18[ndash]875 m were examined. Seventeen sponges, comprising eight species (Ircinia campana, Topsentia sp., Geodia sp., Characella sp., Erylus sp., Apylsina archeri, Cliona sp., and Pheronema carpenteri), and three tunicate colonies (Didemnidae) were fully dissected and all associated organisms were identified and counted. Additionally, the sponges Pheronema annae (951 m) and P. carpenteri (770 m) represent new records for the region. The diversity (H') and density of associates varied considerably among hosts; the densities of associates ranged 0.4[ndash]11,684 per 1 L of host volume.... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330746 Thu, 04 Mar 2010 00:00:00 +0100 3330746 http://www.medworm.com/index.php?rid=3330745&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00185.x Abstract. The nervous system of the meiobenthic priapulid species Tubiluchus troglodytes is described by immunohistochemistry and confocal laser scanning microscopy. The brain is circumpharyngeal, consisting of a central ring of neuropil and both anterior and posterior somata. From the brain emerges a ventral nerve cord, which shows ganglion-like swellings in the neck and caudal region. The introvert includes longitudinal neurite bundles running below and between the rows of scalids, with a small cluster of sensory cells under each scalid. In the body wall of the neck and trunk region, longitudinal and circular neurite bundles are present in an orthogonal pattern. The tail is innervated from the caudal swelling of the ventral nerve cord; it also includes longitudinal and circular bundles i... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330745 Thu, 04 Mar 2010 00:00:00 +0100 3330745 http://www.medworm.com/index.php?rid=3330744&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00186.x Abstract. A new species in the cephalaspidean family Diaphanidae, Toledonia warenella n. sp., is described from New South Wales, Australia. Three-dimensional, computer-aided reconstructions of the anatomy, based on serial histological sections, show that T. warenella n. sp. has some features in common with other diaphanids, including lack of jaws, gizzard plates, or an operculum. A gill was not detected in the mantle cavity, which is dominated by large, triangular, opposed ciliary bands and a kidney with lobed edges. The buccal mass is large with thick, muscular walls, perhaps indicative of a suctorial feeding behavior. Comparison with other diaphanid genera was hindered by lack of detailed published anatomical data, but shell and radula morphology suggests a close relationship between the... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330744 Thu, 04 Mar 2010 00:00:00 +0100 3330744 http://www.medworm.com/index.php?rid=3330743&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00187.x Abstract. Cycliophora is one of the most recently described metazoan phyla and hitherto includes only two species: Symbion pandora and Symbion americanus. With a very complex life cycle, cycliophorans are regarded as an enigmatic group with an uncertain phylogenetic position, although they are commonly considered lophotrochozoan protostomes. In order to extend the database concerning the distribution of immunoreactive substances in the free-swimming chordoid larva of S. pandora, we investigated synapsin immunoreactivity using fluorescence-coupled antibodies in combination with confocal laserscanning microscopy. Moreover, we analyzed the co-localization patterns of synapsin, serotonin, and RFamide-like immunoreactivity in the chordoid larva by 3D imaging technology based on the confocal mic... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330743 Thu, 04 Mar 2010 00:00:00 +0100 3330743 http://www.medworm.com/index.php?rid=3330742&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00188.x We describe the gelatinous egg mass and intracapsular development in the tropical lucinid Phacoides pectinatus. The embryos developed within individual capsules embedded in a large flimsy, spherical mass. Swimming veligers hatch at 198 [mu]m shell length. They did not feed, settled within several days of hatching, and metamorphosis was completed within 2 weeks of hatching. Gelatinous egg masses might be detected in members of more lucinid species if studies of development included field or in vivo observations of reproduction in addition to producing embryos by stripping the gonads. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330742 Thu, 04 Mar 2010 00:00:00 +0100 3330742 http://www.medworm.com/index.php?rid=3330741&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00189.x We examined the brain architecture in different species of Chaetognatha using immunofluorescence methods with a set of nervous system markers and confocal laser-scan microscopic analysis. These markers include antibodies against synaptic proteins, RFamide-related peptides, and tyrosinated tubulin, as well as a marker of cell nuclei. Furthermore, we present a 3D reconstruction based on histological section series. Our results expand the previous knowledge on neuroanatomy in Chaetognatha. We suggest a structural and functional subdivision of the rather complex chaetognath brain into two domains, a posterior domain that may be primarily involved in the integration of sensory input, and an anterior domain that may be involved in the control of the mouthparts and the anterior part of the digest... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330741 Thu, 04 Mar 2010 00:00:00 +0100 3330741 http://www.medworm.com/index.php?rid=3330740&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00190.x Abstract. The current investigation provides the first histomorphological description of the female pallial gonoduct in the muricid mollusc Dicathais orbita, and of sperm passage in the subfamily Rapaninae. Gonoduct anatomy, musculature, and sperm distribution were documented over the annual reproductive cycle to confirm the site of fertilization in members of the Muricidae, provide evidence for sperm storage, and allow subfamilial comparisons in reproductive anatomy and strategies. This approach revealed morphological plasticity of the ingesting gland in D. orbita, which has implications for the use of gonoduct character traits in taxonomic studies of the Muricidae. Other features of subfamilial diagnostic interest, including the ventral channel and both albumen and capsule glands, are hi... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330740 Thu, 04 Mar 2010 00:00:00 +0100 3330740 http://www.medworm.com/index.php?rid=3330739&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00191.x Abstract. The relationship of the polychaete taxa Syllidae and Sphaerodoridae within Phyllodocida is still unresolved: phylogenetic analyses either show them as sister groups or more widely separated. The present article aims to provide information about the structure of the muscular system that could be essential for understanding their relationship. A crucial point is whether the body wall contains circular muscles, which has recently been shown to be absent in more taxa than previously known. The F-actin filaments in members of Myrianida prolifera (Syllidae) and Sphaerodoropsis sp. (Sphaerodoridae) were labeled with phalloidin and their three-dimensional relationships reconstructed by means of confocal laser scanning microscopy. Among the noteworthy differences that emerged between the ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330739 Thu, 04 Mar 2010 00:00:00 +0100 3330739 http://www.medworm.com/index.php?rid=3330738&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00192.x Abstract. The formation of the central nervous system of the stomatopod crustacean Gonodactylaceus falcatus is described by means of antibody stainings against synapsin and [alpha]-tubulin. It is shown that the longitudinal fiber tracts of the ventral nervous system are formed by two centers of origin comprising a number of pioneer neurons, one at the posterior part of the forming brain, the other in the area of the telson anlage at the posteriormost region of the embryo. In addition to the lateral anlagen of the connectives, a median longitudinal nerve is formed beginning in the mandibular segment neuromere. In contrast to those of other segments, the mandibular ganglia are connected by a single commissure. The brain forms a circumoral ring. There is evidence that the deutocerebrum posses... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330738 Thu, 04 Mar 2010 00:00:00 +0100 3330738 http://www.medworm.com/index.php?rid=3330737&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2010.00193.x Abstract. The Porifera represent one of the only two recent nerveless and muscleless metazoan phyla. Nevertheless, sponges provide behavioral, physiological, pharmacological, morphological, and, more recently, an increasing amount of genetic evidence for a paracrine pre-nervous integration system. Although this system might be derived, it allows us to draw conclusions, on the basis of comparative data, about the origin of the nervous system sensu stricto as found in the eumetazoan phyla. The goal of the present review is to compile recent evidence on the sponge integration systems. Based on this framework, new light is also shed on the evolutionary origin of the eumetazoan synaptic nervous systems, which can be regarded to form an evolutionary biochemical continuum with the paracrine signa... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3330737 Thu, 04 Mar 2010 00:00:00 +0100 3330737 http://www.medworm.com/index.php?rid=3055962&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.auindex_1.x (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3055962 Thu, 03 Dec 2009 00:00:00 +0100 3055962 http://www.medworm.com/index.php?rid=3055961&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00181.x Abstract. Fine morphological details of the genitalia have large potential consequences for the understanding of the reproductive biology of a particular species, especially when mating behavioral studies are difficult to conduct. Oonopidae are a highly diverse spider family comprising a variety of species with complex female reproductive systems, which may have evolved under sexual selection by cryptic female choice. The present study describes the female genitalia of five oonopid species belonging to both conventionally recognized subfamilies by means of semi-thin sections and scanning electron microscopy. In addition, the male palps are briefly described. The organization of the female genitalia in Scaphiella hespera and Scaphiella sp. resembles the entelegyne type. A chitinized canal c... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3055961 Thu, 03 Dec 2009 00:00:00 +0100 3055961 http://www.medworm.com/index.php?rid=3055960&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00179.x Abstract. The speciose tropical soft coral genus Sinularia traditionally has been divided into five intrageneric taxonomic groups based on variation in a single morphological character: the shape of the club sclerites (calcite skeletal elements) embedded in the surface tissues of the colony. To test the phylogenetic utility of this system of classification, we used a 735-bp fragment of the octocoral-specific mitochondrial msh1 gene to construct a molecular phylogeny that included 80 of the [sim]150 recognized morphospecies of Sinularia. The msh1 phylogeny recovered five well-supported clades, but they were not congruent with the traditional intrageneric taxonomic groups. Mapping of characters onto the tree suggested that the five major clades plus several additional sub-clades of Sinularia... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=3055960 Sun, 01 Nov 2009 00:00:00 +0100 3055960 http://www.medworm.com/index.php?rid=2943035&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00183.x We present the first report on the use of the non-invasive method of synchrotron X-ray microtomography to model the dynamics and theoretical bite forces of arthropod mouthparts. The nature of the data allowed us to include precise measurements of muscle areas and the spatial geometry of muscle origins and insertions into a biomechanical model of a morphological microstructure. We investigated the functional morphology of the chelicera in the oribatid mite Archegozetes longisetosus (Acari, Oribatida), a model organism for Chelicerata. The chelicera represents a first-class lever; the intrinsic muscular system consists of a feather-shaped depressor with six muscle bundles and a bouquet-shaped levator with 16 bundles. The relative bite forces, as compared with body mass (force/mass2/3), are 3... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2943035 Fri, 30 Oct 2009 00:00:00 +0100 2943035 http://www.medworm.com/index.php?rid=2943038&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00178.x Abstract. The present study documents the pace of accessory gland and testes degeneration in the wasp Vespula vulgaris by means of a histological and metric approach, that has not been carried out for social wasps so far. To a certain extent, comparison is made with the degenerative processes of the mucus glands of the honeybee drone. In V. vulgaris, no generative tissue is left by the end of 9 d of age, and so degeneration is a fast process. The three different parts of the accessory glands (muscle layer, gland epithelium, and lumen) change with respect to age. The secretory cells of the epithelium reach their maximum activity during the first days of adult life, which results in a maximally filled gland lumen by 9 d. We also provide, for the first time, a histological study of testes deg... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2943038 Thu, 29 Oct 2009 00:00:00 +0100 2943038 http://www.medworm.com/index.php?rid=2943037&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00180.x Abstract. Since the 18th century, the medicinal leech Hirudo medicinalis has been thought to comprise a single species with several different color morphs, but recently some of these color morphs have been assigned to separate species based on morphology, geographical distribution, and molecular sequence data. This research was aimed at testing the ability of three of these species, H. medicinalis, Hirudo verbana, and Hirudo orientalis, to interbreed. We found that in the laboratory, all three species were able to mate with each other and produce hybrid offspring. This suggests that the reproductive isolation is not strong among these species of the genus Hirudo. However, fewer offspring were produced from interspecific crosses compared with intraspecific crosses. This decrease of fecundit... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2943037 Thu, 29 Oct 2009 00:00:00 +0100 2943037 http://www.medworm.com/index.php?rid=2943036&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00182.x Abstract. Gonad and pyloric caecum indices are widely used indicators of reproductive effort and nutritional condition in asteroids. Current methods of quantification generally require sacrificing multiple animals and the resulting reduction in local sea star density could have an unintended impact on benthic communities. Using the intertidal sea star Pisaster ochraceus, we developed and tested a method for estimating organ indices through the non-lethal sampling of single arms. Indices estimated via dissections of single arms accurately predicted the values obtained by sacrificing whole animals. In laboratory and field trials, we compared two methods of sampling single arms: (1) arm removal, and (2) organ extraction through an incision (without arm removal). Two years after these treatmen... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2943036 Thu, 29 Oct 2009 00:00:00 +0100 2943036 http://www.medworm.com/index.php?rid=2785400&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00176.x Abstract. Whale carcasses, sunken wood, and cold seeps provide organically enriched oases in the food-limited deep-sea benthos. At three such enriched habitats in Monterey Bay, CA, at a depth of nearly 3000 m, we observed pycnogonids (sea spiders) of at least two species, Colossendeis gigas and C. japonica, feeding on sea anemones that were commonly found there. Submersible remotely operated vehicles provided direct observations of feeding, as well as high definition video and photographic images. We recorded the co-occurrence of both pycnogonids and prey anemones during ten of 12 visits during 2002[ndash]2006. Anemones and pycnogonids were conspicuously more abundant at these oases than in the surrounding benthos. The sedentary anemone Anthosactis pearseae was attached directly to whalebo... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2785400 Thu, 10 Sep 2009 23:00:00 +0100 2785400 http://www.medworm.com/index.php?rid=2765379&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00172.x Abstract. When free-living organisms evolve into symbiotic organisms (parasites, commensals, or mutualists), their bodyplan is often dramatically modified as a consequence. The present work pertains to the study of this process in a group of marine obligate symbiotic worms, the Myzostomida. These are mainly ectocommensals and are only associated with echinoderms, mostly crinoids. Their usual textbook status as a class of the Annelida is generally accepted, although recent molecular phylogenetic studies have raised doubts on their relationships with other metazoans, and the question of their status remains open. Here, we reconstruct the evolution of their bodyplans by mapping 14 external morphological characters (analyzed using scanning electron microscopy) onto molecular phylogenies using ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2765379 Thu, 03 Sep 2009 23:00:00 +0100 2765379 http://www.medworm.com/index.php?rid=2761263&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00177.x Abstract. When individual placozoans, Trichoplax adhaerens, were fed to polyps of the hydroid Podocoryna carnea, the polyps became paralyzed in all 27 trials. In one instance the hydroid polyp died and in five instances a fragment of the placozoan survived. The time to recovery from paralysis varied with the relative size of the polyp and the placozoan. Placozoans were disassociated into separate cells and then reaggregated by centrifugation to produce pellets of tissue lacking the vesicles called shiny spheres, normally abundant in the upper epithelium. We fed pellets of two size classes to the hydroid polyps. When the placozoan pellet was smaller than the hydroid, paralysis was eliminated in nine of ten trials. When the placozoan pellet was comparable in size to the polyp, paralysis occu... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2761263 Wed, 02 Sep 2009 23:00:00 +0100 2761263 http://www.medworm.com/index.php?rid=2761267&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00171.x Abstract. I describe an unusual case of follicular oogenesis in a bivalve, Gaimardia trapesina, a common marine bivalve from the Magellan Region and adjacent Sub-Antarctic waters, whose members brood their developing larvae. The gonad in G. trapesina is an acinus organ that infiltrates the perivisceral connective tissue; the walls of the acini are formed by tall, slender cells with distal nuclei, supported by a thin conjunctive tissue layer. At the onset of vitellogenesis, each developing oocyte becomes surrounded by a one-cell-thick layer of follicle cells, which may originate from the wall of the acinus. The cells form a follicle that completely encompasses single oocytes, except at the basal zone, where oocytes are in contact with the acinus wall. The follicle persists beyond the end of... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2761267 Tue, 01 Sep 2009 23:00:00 +0100 2761267 http://www.medworm.com/index.php?rid=2761266&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00173.x This study assessed the effects of long (LD) or short (SD) days on the conversion of [14C]-glycerol to [14C]-glucose and total lipid concentration in organs of the crab Neohelice granulata challenged by a change in external salinity. In the 20[permil]-acclimated crabs, no difference was found in the concentration of total lipids in the muscle, hepatopancreas, gills, or hemolymph between crabs acclimated to SD or LD. In SD crabs, the total lipid levels in the anterior and posterior gills did not decrease during an osmotic challenge. Only in the posterior gills did the total lipid levels decrease during acclimation to the 34[permil] medium in LD animals. The total lipid concentration in the hemolymph decreased after 1 d of osmotic stress in SD, and increased in the hepatopancreas. In LD crab... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2761266 Tue, 01 Sep 2009 23:00:00 +0100 2761266 http://www.medworm.com/index.php?rid=2761265&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00174.x Abstract. Two small cemented, cryptic, species of Dianadema (Bivalvia: Anomalodesmata: Clavagellidae) have been recorded from shallow waters of the Indian Ocean. These are Dianadema minima and Dianadema mascarensis. A study of their shells and adventitious crypt morphologies, however, suggests that the two species are conspecific, the former name taking precedence. This re-description of D. minima suggests that on settlement, the larva develops a juvenile shell that continues to grow until a length of [sim]9.0 mm is reached, when it secretes around itself a primary calcareous crypt and cements itself ventrally into a concavity in coral rubble. Subsequently, a crown of tubules is secreted from the dorsal surface of the exposed mantle and an adventitious siphonal tube is formed, which is cha... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2761265 Tue, 01 Sep 2009 23:00:00 +0100 2761265 http://www.medworm.com/index.php?rid=2761264&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00175.x This study examined the effects of acute salinity changes on sea stars (Pisaster ochraceus) collected from a high-salinity site (Bamfield, BC) and a low-salinity site (Vancouver, BC). Sea stars from both sites were exposed to salinities ranging 15[ndash]30 psu. Following a 24-h exposure, the osmolality, sodium concentrations, and chloride concentrations in the perivisceral fluid all varied directly with salinity and were very close to the treatment salinities in both the Bamfield and Vancouver sea stars. The righting response (measured as an activity coefficient) was salinity dependent, with the lowest activity levels at a salinity of 15 psu. Activity coefficients did not vary between the two source populations. Feeding rates on mussels were strongly salinity dependent, but the salinity pa... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2761264 Tue, 01 Sep 2009 23:00:00 +0100 2761264 http://www.medworm.com/index.php?rid=2340151&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00160.x Abstract. The ophiuroid Amphipholis kochii is able to detach its central disc from the underlying oral frame in response to external stimuli. In this article we supply new observations on the microanatomy and ultrastructure of the autotomy plane, and of the juxtaligamental system which is believed to bring about connective tissue changes that underpin the detachment process. We correct previous confusion over the innervation of juxtaligamental nodes involved in disc autotomy, provide evidence that juxtaligamental cells are a population of specialized nerve cells, and present observations on changes in the ultrastructure of juxtaligamental cells during autotomy, which support the view that they are responsible for connective tissue disruption. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2340151 Sat, 18 Apr 2009 04:00:00 +0100 2340151 http://www.medworm.com/index.php?rid=2340152&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00158.x Abstract. Pomacea canaliculata is an internally fertilizing gastropod that produces, besides fertilizing sperm (=eusperm), a large number of unfertile sperm (=parasperm) that have no chromatin, are fusiform, and have three to five flagella. Here, we report that this snail also produces another type of parasperm, which results from a peculiar spermiogenesis including an anterior cytoplasmic migration. The mature oligopyrene parasperm has: (1) a rounded head including a partly lysed nucleus, (2) a conical mid-piece with eight large mitochondrial structures, and (3) a single flagellum ([sim]20 [mu]m). These characteristics, although not found in any other gastropod parasperm, are shared with the externally fertilizing "ectaquasperm" and with the early spermiogenic stages of internally fertili... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2340152 Wed, 15 Apr 2009 04:00:00 +0100 2340152 http://www.medworm.com/index.php?rid=2325800&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00170.x Abstract. The majority of tagged colonies of Pseudoplexaura porosa in Bermuda were reproductive over 2 months in the summer. They spawned 5[ndash]8 d after the full moon, with a peak on the sixth day, similar to colonies in Panama. The months of spawning were August and September in 1998, but July and August in 1999 and 2000. This temporal difference between the months of spawning corresponded to inter-annual variations in seawater temperature profiles. Initial gamete development each year occurred only when the daily mean seawater temperature during the month before spawning exceeded 27°C. There was a significant positive relationship between reproductive effort (gamete volume) of colonies and rising seawater temperature in the month preceding spawning; this was true for both the initial... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2325800 Sat, 11 Apr 2009 04:00:00 +0100 2325800 http://www.medworm.com/index.php?rid=2325820&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00166.x Abstract. Many hermaphroditic species are promiscuous, have a sperm digesting organ and an allosperm storage organ (i.e., spermatheca) with multiple compartments (i.e., spermathecal tubules) providing opportunities for sperm competition. The relative paternity of a sperm donor drives the evolution of mating behaviors that allow manipulation of the sperm receiver's reproductive behavior or physiology. We studied the relationship between sperm transfer, sperm storage, sperm digestion, and copulation duration in the hermaphroditic land snail Succinea putris, in which an active individual mates on top of a passive individual. Specifically, we examined (i) whether the entire copulation duration was required to complete reciprocal sperm transfer, (ii) sperm transfer patterns and their relationsh... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2325820 Tue, 31 Mar 2009 04:00:00 +0100 2325820 http://www.medworm.com/index.php?rid=2325816&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00167.x We describe these pappose setae and document the occurrence of similar setae in 36 other decorating majoids across seven families. In O. gracilis, the density of pappose and hooked setae independently covary with decoration amount, which is sexually dimorphic[mdash]juveniles and adult females decorate heavily, whereas adult males decorate sparsely. Adult males have reduced numbers of hooked and pappose setae, but the ontogenetic patterns for the two setal types are different, suggesting that they are quasi-independent characters. We experimentally ablated pappose setae to ask if they functionally contribute to decorating in O. gracilis. Surprisingly, we found that pappose setae are not necessary for decorating under laboratory conditions. Pappose setae could play an auxiliary mechanical ro... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2325816 Tue, 31 Mar 2009 04:00:00 +0100 2325816 http://www.medworm.com/index.php?rid=2325812&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00161.x Abstract. Larval gut characters of 45 species of black flies, representing 17 subgenera and 15 genera, were studied for their utility in taxon diagnosis and phylogenetic inference. Phase-contrast and scanning electron microscopy revealed a wealth of new characters in the esophageal armature of the foregut. Larval gut morphology, particularly characters of the esophageal armature, varied significantly among taxa, permitting generic diagnoses. A cladogram inferred from 13 gut characters supported a sister-group relationship between Parasimulium and the remaining simuliids, but did not show a strong phylogenetic signal for the current, well-supported concept of tribal level monophyly. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2325812 Tue, 31 Mar 2009 04:00:00 +0100 2325812 http://www.medworm.com/index.php?rid=2325808&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00168.x Abstract. Population size, reproductive timing and habitats, seasonal behaviors, and juvenile activity were assessed in a British Columbia population of the endangered Oregon forestsnail, Allogona townsendiana, over a period of 4 years. Adult snail population size ranged from seven to 47 snails in four × 24-m2 sampling sites. The mating period peaked in March and April; adults aggregated in clusters of eight to 14 snails before mating. Pairs of snails were observed to mate for 225 min or more in close proximity to coarse woody debris and stinging nettle, Urtica dioica. Nesting peaked in April[ndash]May and resulted in a mean clutch size of 34 eggs (SD=9). Hatching for two nests occurred at 63 and 64 d after oviposition. Within hours of hatching, juveniles began dispersing from the nest si... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2325808 Tue, 31 Mar 2009 04:00:00 +0100 2325808 http://www.medworm.com/index.php?rid=2325804&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2009.00169.x This study indicates that members of G. insolitus are commensal upon larger crayfish species, using their burrows to survive the seasonal drying of their habitat. Conservation strategies for populations of G. insolitus will need to consider co-existing species of burrowing crayfish. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2325804 Tue, 31 Mar 2009 04:00:00 +0100 2325804 http://www.medworm.com/index.php?rid=2258071&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00165.x Abstract. In laboratory studies of fertilization using the gonochoric broadcast-spawning asterinid sea star Patiria miniata, we found many cases in which some mature eggs spawned by females formed cleavage-stage embryos and feeding bipinnaria larvae without fertilization by sperm. Segregation of maternal microsatellite alleles among the parthenogenetic offspring of known heterozygous females was consistent with several specific modes of asexual reproduction, including polar body suppression. Cryptic outcrossing by sperm contamination was ruled out by the failure to observe non-maternal alleles. The potential for asexual reproduction by the normally outcrossing members of P. miniata may suggest a shared propensity for asexuality among asterinid species from several clades in which isolated ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2258071 Fri, 13 Mar 2009 04:00:00 +0100 2258071 http://www.medworm.com/index.php?rid=2258074&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00157.x In this study, geometric morphometric analysis employing landmark data is used to quantify both intra- and interspecific variation in this genus. The large amount of variation is condensed into two or three groups depending on the structures examined, and these groups correspond to either the two species or to previously established mitochondrial DNA clades within one of the species. The results also show that analyses of female structures do not separate the groups as readily as the analyses of the male structures. The large amount of variation present in some structures is not correlated with geography or population genetic structure. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2258074 Wed, 11 Mar 2009 04:00:00 +0100 2258074 http://www.medworm.com/index.php?rid=2258073&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00159.x We present a new method of tagging using sequential fluorochrome markers, as well as a more precise method of quantifying growth. Such polyfluorochromes enable repeated markings that allow measurement of multiple growth points and unique identification of individuals or groups. We marked sea urchins, Strongylocentrotus droebachiensis, with four fluorochromes: alizarin complexone, calcein, calcein blue, and tetracycline. All fluorochromes marked both by injection and immersion. We examined the clarity of the mark produced with low, metabolically scaled doses, and higher doses similar to those that have been previously used. We tested the effect of fluorochromes on survival, growth, jaw size, and gonad size by marking a size range (3.9[ndash]44.3 mm in diameter) of urchins with either one or... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2258073 Wed, 11 Mar 2009 04:00:00 +0100 2258073 http://www.medworm.com/index.php?rid=2258072&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00162.x Abstract. Here we describe the hatching and morphology of the earliest larval stages of the priapulid worm Priapulus caudatus for the first time. The hatching larva differs considerably from previously described larvae not only in its general body shape but also in its lack of a proper lorica including the typical lorica tubuli. Furthermore, no mouth opening or pharyngeal teeth have formed as yet, and the number and arrangement of scalids differ from that of later larvae. The hatching larva molts and emerges as the first lorica larva. This larva partially resembles earlier described lorica larvae, but there are a number of important differences; the first lorica larva is smaller, and the mouth opening as well as pharyngeal teeth are still yet to form. The second lorica larva is equipped wi... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2258072 Wed, 11 Mar 2009 04:00:00 +0100 2258072 http://www.medworm.com/index.php?rid=2143852&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00150.x Abstract. The predominance of sexuality in eukaryotes remains an evolutionary paradox, given the "two-fold cost of sex" of sex also known as the "cost of males." As it requires two sexual parents to reproduce and only one parthenogenetic parent, parthenogens should have twice the reproductive rate compared with their sexual counterparts and their genes should spread twice as fast, if all else is equal. Yet, parthenogenesis is relatively rare and considered an evolutionary dead-end, while sexuality is the dominant form of reproduction in multicellular eukaryotes. Many studies have explored short-term benefits of sex that could outweigh its two-fold cost, but few have compared fecundity between closely related sexuals and parthenogens to first verify that "all else is equal" reproductively. ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2143852 Fri, 30 Jan 2009 04:25:46 +0100 2143852 http://www.medworm.com/index.php?rid=2080301&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00153.x Abstract. Tunic cells are free cells distributed in the tunic, the integumentary matrix of tunicates. In ascidians, various types of tunic cells have been described both in solitary and in colonial species. Many of them are functionally specialized and are related to the protection of the animal, such as phagocytosis to prevent infection, acid storage to avoid predation, and pigmentation to protect against solar radiation. While some tunic cells are known to play a role in colonial allorecognition, bioluminescence, and algal symbiosis, the functional roles of many cell types still remain to be determined. The composition of tunic-cell types varies among ascidian species, most likely reflecting the functional requirements of the tunic in each species. Although some cell types, e.g., tunic n... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2080301 Tue, 06 Jan 2009 04:42:54 +0100 2080301 http://www.medworm.com/index.php?rid=2080304&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00149.x Abstract. The syllid polychaete Odontosyllis phosphorea produces brilliant displays of green bioluminescence during mating swarms. We studied freshly collected individuals of O. phosphorea in the laboratory to understand the characteristics of its luminescent system. Light emission appeared as an intense glow after stimulation with potassium chloride, and was associated with secreted mucus. The mucus was viscous, blue in color, and exhibited a long-lasting glow that was greatly intensified by addition of peroxidase or ammonium persulfate. The emission spectrum of mucus-associated bioluminescence was unimodal, with a maximum emission in the green spectrum between 494 and 504 nm. The fluorescence emission spectrum was similar, but the fluorescence intensity was low unless it originated from ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2080304 Mon, 05 Jan 2009 05:00:00 +0100 2080304 http://www.medworm.com/index.php?rid=2080303&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00151.x Abstract. Diminished populations of eastern oysters Crassostrea virginica in Chesapeake Bay have stimulated proposals to introduce Crassostrea ariakensis from Asia to restore oyster stocks. As part of a program evaluating possible ramifications of such an introduction, we studied how invertebrate predators responded to this non-native oyster. We compared predation activity under laboratory conditions by oyster drills (Urosalpinx cinerea; Eupleura caudata) that bore through an oyster's shell and by the seastar Asterias forbesi that pulls shell valves apart. These three predators preyed significantly (p (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2080303 Mon, 05 Jan 2009 05:00:00 +0100 2080303 http://www.medworm.com/index.php?rid=2080302&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00152.x Abstract. Octopodids are a globally distributed group of marine molluscs. Despite this, our knowledge of their reproductive biology rests heavily on inference, as all phases of copulation, beginning with sperm transfer, occur within the mantle cavity. Male octopuses insert a spermatophore into the female's oviduct, which is predicted to release a sperm-filled sac that either bursts to release sperm for storage or to itself be stored in a gland in the middle of the oviduct. To test whether female octopuses use sperm from multiple males to fertilize their eggs, as may be predicted from anatomy and anecdotal accounts, we apply microsatellite analysis to a partial clutch of Graneledone boreopacifica collected at 1600-m depth to test for multiple paternity. At least two genetically distinct sir... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=2080302 Mon, 05 Jan 2009 05:00:00 +0100 2080302 http://www.medworm.com/index.php?rid=1840102&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00147.x Abstract. Sea urchin embryos form an endoskeletal spicule composed of calcium carbonate and occluded matrix proteins. The accumulation of the LSM34 spicule matrix protein in embryos of Lytechinus pictus (and its ortholog, SpSM50, in Strongylocentrotus purpuratus) has been inhibited using morpholino antisense oligonucleotides. The inhibition, using relatively high levels of antisense reagent, can result in the complete absence of spicules, and the complete loss of immunoreactive LSM34/SpSM50, as judged by immunostaining and Western blotting. Primary mesenchyme cells (PMCs) do form and express PMC-specific cell surface antigens despite this inhibition. However, these anti-LSM34/SpSM50-treated embryos do not accumulate SM30 protein, another major matrix protein. Hence, both the initiation of ... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1840102 Wed, 01 Oct 2008 04:00:00 +0100 1840102 http://www.medworm.com/index.php?rid=1840103&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00148.x Abstract. The differentiation of the female reproductive system from a macroscopic and microscopic point of view was studied in Cherax quadricarinatus. For this characterization, 184 females were dissected and processed for the histological analysis. From the differentiation of the ovary up to its maturity, three ovarian morphotypes could be distinguished macroscopically: parallel strands without any contact between them, an H-shaped ovary, and a Y-shaped ovary. These morphotypes were compared within the Astacida. Four ovarian developmental stages were recognized based on ovary color, and the histological structure and relative proportion of cellular types. The post-spawning ovary was also characterized. The components of the female reproductive system sheath were described and its modific... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1840103 Tue, 30 Sep 2008 04:00:00 +0100 1840103 http://www.medworm.com/index.php?rid=1713097&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00146.x Abstract. The starlet sea anemone, Nematostella vectensis Stephenson 1935, is a burrowing, estuarine species that has become a model organism for fundamental studies of cnidarian and metazoan development. During early oogenesis, oocytes appear in the basal region of the gastrodermis in the reproductive mesenteries and gradually bulge into the adjacent connective tissue space (mesoglea) where the majority of oocyte growth and vitellogenesis occurs. However, oocytes do not physically contact the cellular and amorphous matrix of the mesogleal compartment due to a thin, intervening basal lamina. Oocytes retain limited contact with the basal gastrodermal epithelium via groups of ultrastructurally modified gastrodermal cells called trophocytes. Trophocytes are monociliated accessory cells of som... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1713097 Tue, 19 Aug 2008 04:00:00 +0100 1713097 http://www.medworm.com/index.php?rid=1699520&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00143.x We examined the soft tissues of live freshwater mussels, Eastern elliptio Elliptio complanata, via magnetic resonance imaging (MRI), acquiring data with a widely available human whole-body MRI system. Anatomical features depicted in the profile images included the foot, stomach, intestine, anterior and posterior adductor muscles, and pericardial cavity. Noteworthy observations on soft tissue morphology included a concentration of lipids at the most posterior aspect of the foot, the presence of hemolymph-filled fissures in the posterior adductor muscle, the presence of a relatively large hemolymph-filled sinus adjacent to the posterior adductor muscle (at the ventral-anterior aspect), and segmentation of the intestine (a diagnostic description not reported previously in Unionidae). Relative... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1699520 Wed, 13 Aug 2008 04:00:00 +0100 1699520 http://www.medworm.com/index.php?rid=1614393&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00145.x Abstract. The phylogenetic position of Polygordius is still pending; relationships with either Opheliidae or with Saccocirrus are the most favored hypotheses. The present study of Polygordius appendiculatus was designed to look for morphological characters supporting either of these two hypotheses. The homology of the anterior appendages, and the structure of the central nervous system and nuchal organ all required clarification; we also examined whether photoreceptor-like sense organs exist in adults. From their innervation pattern, it is likely that the anterior appendages represent palps. They lack structures typical of palps in Canalipalpata, such as musculature and coelomic cavities, which would be expected in the case of a saccocirrid relationship. Thirteen photoreceptor-like sense o... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1614393 Sun, 13 Jul 2008 04:00:00 +0100 1614393 http://www.medworm.com/index.php?rid=1614394&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fdx.doi.org%2F10.1111%252Fj.1744-7410.2008.00144.x Abstract. Freshwater crayfishes of the genus Parastacus are intersex, i.e., show characteristics of both sexes in the same individual; also, intersexuality has been documented in hermaphroditic species. The aim of this study was to analyze the gonads of Parastacus varicosus, characterizing its sexual pattern. The animals were collected at Cova do Touro, Gravataí, Rio Grande do Sul, Brazil. Three sexual forms were identified: intersex females, intersex males, and transitional specimens showing an ovotestes gonad that could only be identified by means of histological analysis. All specimens had two pairs of gonopores and gonoducts. The oviduct had a wider diameter in females, whereas in males the vasa deferentia were more developed. Gonads were composed of two parallel structures located in... Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1614394 Thu, 10 Jul 2008 04:00:00 +0100 1614394 http://www.medworm.com/index.php?rid=1422038&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00123.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The ultrastructure of the tegument in Paraechinophallus japonicus (Bothriocephalidea: Echinophallidae), a cestode parasite of the bathypelagic fish Psenopsis anomala, was studied using scanning and transmission electron microscopy. ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1422038 Mon, 05 May 2008 19:59:07 +0100 1422038 http://www.medworm.com/index.php?rid=1422039&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00133.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The timing and spatial distribution of cells containing FMRFamide-related molecules in the embryogenesis of the polychaete Ophryotrocha labronica were studied immunocytochemically. FMRFamide-like molecules emerge early during embryonic ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1422039 Mon, 05 May 2008 13:41:12 +0100 1422039 http://www.medworm.com/index.php?rid=1422040&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00142.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Male crickets produce conspicuous acoustic signals to attract mates and deter potential rivals. These signals are created when a male cricket closes his wings rapidly and a file and scraper mechanism causes several areas of the wing to ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1422040 Mon, 05 May 2008 13:41:10 +0100 1422040 http://www.medworm.com/index.php?rid=1422042&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00140.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Aspects of the life cycle of the peritrich ciliate Zoothamnium intermedium, an epibiont on calanoid copepods in the Chesapeake Bay, were investigated using host and epibiont cultures. Experiments were designed to characterize the formation, ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1422042 Mon, 05 May 2008 13:41:09 +0100 1422042 http://www.medworm.com/index.php?rid=1422041&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00139.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Members of Odontocymbiola magellanica (Volutidae, Odontocymbiolinae) inhabit Argentinean waters from 35°S to the Magallanes Strait. The reproductive biology of this potential fishery resource has not been studied before. Male individuals reach ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1422041 Mon, 05 May 2008 13:41:09 +0100 1422041 http://www.medworm.com/index.php?rid=1422043&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00141.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The marine snail Trichotropis cancellata possesses hairy projections of periostracum (outer shell layer) whose function is unknown. Although rigid shell projections in molluscs have been studied extensively, the selective advantage of flexible ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1422043 Mon, 05 May 2008 13:41:08 +0100 1422043 http://www.medworm.com/index.php?rid=1409081&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00118.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Light and electron microscopy were used to characterize the structure of secretory cells and their products involved in attachment of two monogenean parasites of fish, in order to understand their role in the attachment process. In ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409081 Wed, 30 Apr 2008 18:44:46 +0100 1409081 http://www.medworm.com/index.php?rid=1409082&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00119.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Polyclad flatworms are acoelomate bilaterians found in benthic communities worldwide, predominantly in marine environments. Current polyclad systematics is unstable, with two non-concordant classification schemes resulting in a poor ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409082 Tue, 29 Apr 2008 19:48:32 +0100 1409082 http://www.medworm.com/index.php?rid=1409083&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00136.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Intersexes are common in crustaceans. Typically, these intersexes are sterile or function as females, but prior evidence from laboratory experiments suggests that intersexes of a key species of gammaridean amphipod, Corophium volutator, might ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409083 Tue, 29 Apr 2008 19:43:32 +0100 1409083 http://www.medworm.com/index.php?rid=1409084&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00134.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Larval development of a small ovoviviparous comatulid crinoid, Aporometra wilsoni, was investigated using a population from South Australia. The genital pinnules of reproductive females each contain an ovary, within which are oocytes of ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409084 Tue, 29 Apr 2008 19:43:29 +0100 1409084 http://www.medworm.com/index.php?rid=1409085&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00138.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Parasites can influence the population dynamics of their hosts by affecting life-history strategies and behavior. The hematophageous mite Riccardoella limacum lives in the lung cavity of terrestrial gastropods. We used correlational and ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409085 Tue, 29 Apr 2008 19:43:20 +0100 1409085 http://www.medworm.com/index.php?rid=1409086&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00137.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The morphology of the obligately ectoparasitic polychaete Asetocalamyzas laonicola was studied by light and electron microscopy, and its taxonomic position was determined using molecular methods. The parasite has an extensive coelomic cavity, ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409086 Tue, 29 Apr 2008 19:43:13 +0100 1409086 http://www.medworm.com/index.php?rid=1409087&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00135.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. We compared growth rates and final morphological states of the athecate colonial hydroid Podocoryna carnea in two nutritional environments: one varying the quantity of food provided at a fixed interval and the second varying the time between ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1409087 Tue, 29 Apr 2008 19:43:09 +0100 1409087 http://www.medworm.com/index.php?rid=1372875&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00128.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The reproductive cycles of four Mediterranean demosponges (Axinella damicornis, Corticium candelabrum, Raspaciona aculeata, and Chondrosia reniformis) were investigated during 2 consecutive years. Three of the species had annual gametogenic ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372875 Tue, 15 Apr 2008 18:56:08 +0100 1372875 http://www.medworm.com/index.php?rid=1372876&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00131.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR This article examines the eyes of the moth Operophtera brumata, in which only the males have wings. Both sexes possess eyes of the superposition type, have facets with corneal nipples, and ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372876 Tue, 15 Apr 2008 01:45:48 +0100 1372876 http://www.medworm.com/index.php?rid=1372877&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00129.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. For simultaneous hermaphrodites, a male-to-female shift in sex allocation with growth, and weak sexual selection on the male function, is predicted by many theories, although empirical data for both predictions are insufficient for internally ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372877 Tue, 15 Apr 2008 01:45:47 +0100 1372877 http://www.medworm.com/index.php?rid=1372878&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00125.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Many animals have the ability to delay metamorphosis when conditions are unfavorable. This strategy carries obvious benefits, but may also result in severe consequences for lecithotrophic larvae that run low on time and energy. Precocious ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372878 Tue, 15 Apr 2008 01:45:42 +0100 1372878 http://www.medworm.com/index.php?rid=1372879&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00132.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Male polyps of the antipatharian Cirrhipathes sp., collected along the coral reef of Siladen Island (Sulawesi, Indonesia), were studied in order to gain an insight into the reproductive biology. Spermatocysts (maximum size 120 μm) are located ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372879 Tue, 15 Apr 2008 01:45:40 +0100 1372879 http://www.medworm.com/index.php?rid=1372880&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00126.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Medusae were the earliest animals to evolve muscle-powered swimming in the seas. Although medusae have achieved diverse and prominent ecological roles throughout the world's oceans, we argue that the primitive organization of cnidarian muscle ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372880 Tue, 15 Apr 2008 01:45:37 +0100 1372880 http://www.medworm.com/index.php?rid=1372881&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00130.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Crustaceans in the class Branchiopoda exhibit a wide range of breeding systems, including dioecy (gonochorism), androdioecy, parthenogenesis, cyclic parthenogenesis, and hermaphroditism. The largest subgroup of the Branchiopods, the ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372881 Tue, 15 Apr 2008 01:45:35 +0100 1372881 http://www.medworm.com/index.php?rid=1372882&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2008.00127.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Phenotypic plasticity is the ability of some organisms to exhibit different phenotypes in response to environmental conditions. Many sessile marine invertebrates are morphologically plastic. In colonial cnidarians, compact morphologies are ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1372882 Tue, 15 Apr 2008 01:45:34 +0100 1372882 http://www.medworm.com/index.php?rid=1310310&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00117.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 127, Issue 1, Page 80-86, Winter 2008. Abstract. Two species of earthworms were used to unravel why some earthworm species crawl out of the soil at night after heavy rain. Specimens of Amynthas gracilis, which show this behavior, were found to have poor tolerance to water immersion and a ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1310310 Tue, 18 Mar 2008 06:35:46 +0100 1310310 http://www.medworm.com/index.php?rid=1277139&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00121.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Males are predicted to strategically allocate sperm across mating partners in order to maximize their chances of paternity. This requires that males have the ability to detect aspects of their partner's mating history or the number of ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1277139 Tue, 04 Mar 2008 19:53:32 +0100 1277139 http://www.medworm.com/index.php?rid=1277140&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00122.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The sexual system of two peppermint shrimps, Lysmata bahia and Lysmata intermedia, inhabiting intertidal fossil coral terraces at Bocas del Toro, on the Caribbean coast of Panama, was examined. Dissections suggested that the population of each ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1277140 Tue, 04 Mar 2008 00:08:50 +0100 1277140 http://www.medworm.com/index.php?rid=1277141&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00120.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Two new families of amphiboloid gastropods were recently erected, largely due to the very distinct structural and functional configurations of their distal reproductive systems. The spermovipositors in monaulic Salinator spp. (Amphibolidae) ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1277141 Tue, 04 Mar 2008 00:08:44 +0100 1277141 http://www.medworm.com/index.php?rid=1277142&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00124.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The anterior median artery is an unpaired vessel that leaves the anterior end of the lobster (Homarus americanus) heart and supplies hemolymph to the brain, the antennae, and the eyestalks. This vessel has a trilaminar organization, consisting ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1277142 Tue, 04 Mar 2008 00:08:40 +0100 1277142 http://www.medworm.com/index.php?rid=1108037&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00106.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Bryozoans are among a diverse range of invertebrates capable of secreting calcium carbonate skeletons. Relatively little is known about biomineralization in bryozoans, despite the importance of understanding biomineralization processes for ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108037 Thu, 20 Dec 2007 19:08:39 +0100 1108037 http://www.medworm.com/index.php?rid=1108038&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00110.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. Ophiopeza spinosa, a small ophiodermatid ophiuroid, is locally abundant in shallow water rubble habitat at Lizard Island, northern Great Barrier Reef, Australia. This species is a protantric hermaphrodite. The switch from reproduction as a ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108038 Thu, 20 Dec 2007 18:39:16 +0100 1108038 http://www.medworm.com/index.php?rid=1108039&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00112.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The phylogenetic relationships within the Order Aplousobranchiata (Ascidiacea) are largely unexplored. In this work, we study the phylogenetic status of the genera Clavelina and Pycnoclavella. Traditionally, both genera had been included in ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108039 Thu, 20 Dec 2007 18:39:14 +0100 1108039 http://www.medworm.com/index.php?rid=1108040&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00104.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. We have collected evidence that the nominal species, Polydora cornuta Bosc 1802, contains at least three separate species in North America. Specimens of P. cornuta were collected in California, Florida, and Maine, raised in the laboratory, and ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108040 Thu, 20 Dec 2007 18:39:07 +0100 1108040 http://www.medworm.com/index.php?rid=1108041&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00109.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR In this study, we describe and quantify survivorship of early stages of ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108041 Thu, 20 Dec 2007 18:39:06 +0100 1108041 http://www.medworm.com/index.php?rid=1108042&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00111.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The reproductive anatomy of gastrotrichs is well known for several species, especially for the marine taxon Macrodasyida. However, there is little information on the reproductive organs and the modes of mating and sperm transfer in putative ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108042 Thu, 20 Dec 2007 18:39:04 +0100 1108042 http://www.medworm.com/index.php?rid=1108043&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00113.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. The ribbon-shaped salivary glands in Bulla striata were studied with light microscopy and transmission electron microscopy (TEM). Secretion is produced in tubules formed by two types of secretory cells, namely granular mucocytes and vacuolated ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108043 Thu, 20 Dec 2007 18:39:01 +0100 1108043 http://www.medworm.com/index.php?rid=1108044&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00114.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 0, Issue 0, Page ???, OnlineEarly Articles. Abstract. In marine soft-sediment habitats, tissue loss by infuanal invertebrates can provide significant energetic input to higher trophic levels, have substantial impacts on individual behavior, growth, and fecundity, and resulting changes in ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1108044 Thu, 20 Dec 2007 18:38:59 +0100 1108044 http://www.medworm.com/index.php?rid=1089778&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00099.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 126, Issue 4, Page 287-294, Fall 2007. Abstract. Paramecium bursaria, a freshwater protozoan, typically harbors hundreds of symbiotic algae (Chlorella sp.) in its cytoplasm. The relationship between host paramecia and symbiotic algae is stable and mutually beneficial in natural environments. ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1089778 Wed, 12 Dec 2007 19:13:23 +0100 1089778 http://www.medworm.com/index.php?rid=1089786&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00115.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 126, Issue 4, Page 396, Fall 2007. (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1089786 Tue, 11 Dec 2007 19:17:34 +0100 1089786 http://www.medworm.com/index.php?rid=1089784&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00107.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 126, Issue 4, Page 373-384, Fall 2007. Abstract. Glacial cycles and other climatic events have been widely invoked as factors promoting divergence, secondary contact, and hybridization between populations of terrestrial organisms, but the origin and fate of secondary contact in the sea is ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1089784 Tue, 11 Dec 2007 19:17:34 +0100 1089784 http://www.medworm.com/index.php?rid=1089783&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00105.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 126, Issue 4, Page 366-372, Fall 2007. Abstract. In the newly hatched larva in Allacma fusca, the midgut epithelium was fully developed and formed by flattened epithelial cells surrounding the yolk mass in the midgut lumen. Immediately after hatching, the first larva began to feed; the migut ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1089783 Tue, 11 Dec 2007 19:17:34 +0100 1089783 http://www.medworm.com/index.php?rid=1089785&cid=s_32044_62_f&fid=32044&url=http%3A%2F%2Fwww.blackwell-synergy.com%2Fdoi%2Fabs%2F10.1111%2Fj.1744-7410.2007.00108.x%3Fai%3Dfty%26mi%3D4mpuw%26af%3DR Invertebrate Biology, Volume 126, Issue 4, Page 385-395, Fall 2007. Abstract. "Babysitting" symbioses between brittle star species involve juveniles of one species and adults of another. During this phenomenon, reported from many localities in the Indo-Pacific Ocean, juveniles are attached to the disk or lie in the ... (Source: Invertebrate Biology) Invertebrate Biology journals http://www.medworm.com/rss/comments.php?id=1089785 Tue, 11 Dec 2007 19:17:33 +0100 1089785