Invertebrate Biology最新文献

{"title":"Sex-specific differences in gonopore and gonadal growth trajectories in the brooding sea urchin, Abatus cavernosus (Spatangoida)","authors":"Damián G. Gil,&nbsp;Héctor E. Zaixso,&nbsp;Javier A. Tolosano","doi":"10.1111/ivb.12278","DOIUrl":"10.1111/ivb.12278","url":null,"abstract":"<p>The heart urchin <i>Abatus cavernosus</i> shows sexual dimorphism characterized by the development of external brood pouches and the enlargement of gonopores in brooding females. Relationships between body size, gonopore size, and gonadal maturation in each sex were examined for inflection points using piecewise regression models (PRM). Opening of the gonopore occurred at 15.5 mm test length. Inflection points in the gonadal growth and gonopore diameter trajectories were clustered at smaller sizes in males (23 and 24.2 mm, respectively) than in females (25.1 and 25.9 mm), indicating sex-specific differences in sexual maturation. Gonopore growth showed positive allometry at pre-adult stages of development in both sexes, but isometry and negative allometry in adult females and males, respectively. Gonadal growth was initiated at smaller sizes and proceeded at a higher rate with increasing body size in males than in females. Identification of inflection points in gonopore and gonadal growth trajectories, using objective PRM, allows the determination of life stages and sexual maturation for individuals, thus providing a complementary tool for population studies.</p>","PeriodicalId":54923,"journal":{"name":"Invertebrate Biology","volume":"139 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/ivb.12278","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49060001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"General characterization of regeneration in Aeolosoma viride (Annelida, Aeolosomatidae)","authors":"Chiao-Ping Chen,&nbsp;Sheridan Ke-Wing Fok,&nbsp;Yu-Wen Hsieh,&nbsp;Cheng-Yi Chen,&nbsp;Fei-Man Hsu,&nbsp;Yao-Hsiang Chang,&nbsp;Jiun-Hong Chen","doi":"10.1111/ivb.12277","DOIUrl":"10.1111/ivb.12277","url":null,"abstract":"<p>Regeneration has long been the focus of scientific interest for its potential to restore lost, damaged, or aged tissues and organs. A wide range of regenerative studies have been conducted on different vertebrate and invertebrate model organisms. Annelids are known for their regenerative capacities, and because of their relatively complex organ systems, they are an ideal organism for regeneration study. Our present work focused on the freshwater annelid <i>Aeolosoma viride</i>, an asexually reproducing annelid capable of regenerating both anteriorly and posteriorly. Even though regenerative ability has been documented in this animal in previous studies, detailed characterization of the process is still unavailable. The objective of this study was to evaluate the regenerative ability of <i>A. viride</i>. We described the sequential morphological events during the process of regeneration, such as wound healing and the formation of blastema, mouth, and pygidium. In order to clarify the capacity and type of regeneration, we conducted a series of observations and experiments using a cell proliferation assay. Massive proliferation and the absence of cell migration indicated that the animal regenerates primarily through epimorphosis. Our study of the epimorphic regenerative process of <i>A. viride</i> provides a clearer picture of the evolutionary origin of regeneration in annelids.</p>","PeriodicalId":54923,"journal":{"name":"Invertebrate Biology","volume":"139 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/ivb.12277","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49350043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of mating on female reproduction across hermaphroditic freshwater snails","authors":"Elferra M. Swart,&nbsp;Naima C. Starkloff,&nbsp;Sanne Ypenburg,&nbsp;Jacintha Ellers,&nbsp;Nico M. van Straalen,&nbsp;Joris M. Koene","doi":"10.1111/ivb.12275","DOIUrl":"10.1111/ivb.12275","url":null,"abstract":"<p>Sexual conflicts often arise between mating partners because each sex tries to maximize its own reproductive success. One major male strategy to influence a partner's resource allocation is the transfer of accessory gland proteins. This has been shown to occur in simultaneous hermaphrodites as well as in organisms with separate sexes. Although accessory gland proteins affect the investment of resources in both male and female function, we here specifically focus on female investment. In the great pond snail, <i>Lymnaea stagnalis</i>, previous studies found that the accessory gland protein ovipostatin reduced female fecundity by suppressing egg laying in the partner in the short term (days). To investigate whether this reduction in egg laying is a commonly found effect of mating in freshwater snails, we compared egg output for evidence of suppression in isolated and paired snails of eight pulmonate species. Furthermore, we determined whether the suppression of egg laying caused a shift in resource allocation to the eggs. We found that in five of the eight species egg laying was suppressed, with fewer and lighter egg masses being laid when they had access to a mating partner. In mated pairs of <i>L. stagnalis</i> and <i>Biomphalaria alexandrina</i>, allocation of resources to the eggs was altered in opposite ways: individuals of <i>L. stagnalis</i> laid fewer but larger and heavier eggs; individuals of <i>B. alexandrina</i> laid smaller and lighter eggs, with no change in egg numbers. Such changes in the female function are most likely the result of combined effects of receiving accessory gland proteins, and the cost of mating in both male and female roles. Thus, effects of the maternal environment, including the receipt of accessory gland proteins, on offspring investment are not restricted to species with separate sexes.</p>","PeriodicalId":54923,"journal":{"name":"Invertebrate Biology","volume":"139 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/ivb.12275","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42917426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large-scale ciliary reversal mediates capture of individual algal prey by Müller's larva","authors":"George von Dassow,&nbsp;Christina I. Ellison","doi":"10.1111/ivb.12274","DOIUrl":"10.1111/ivb.12274","url":null,"abstract":"<p>We documented capture of microalgal prey by several species of wild-caught Müller's larvae of polyclad flatworms. To our knowledge, this is the first direct observation of feeding mechanism in this classical larval type. High-speed video recordings showed that virtually all captures were mediated by large-scale transient ciliary reversal over one or more portions of the main ciliary band corresponding to individual lobes or tentacles. Local ciliary beat reversals altered near-field flow to suck parcels of food-containing water mouthward. Many capture episodes entailed sufficient coordinated flow disruption that these compact-bodied larvae tumbled dramatically. Similar behaviors were recorded in at least four distinct species, one of which corresponds to the ascidian-eating polyclad <i>Pseudoceros canadensis</i>.</p>","PeriodicalId":54923,"journal":{"name":"Invertebrate Biology","volume":"139 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/ivb.12274","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44413197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Embryonic development of the false limpet Siphonaria lateralis from Atlantic Patagonia","authors":"Soledad Zabala,&nbsp;Andrés Averbuj,&nbsp;Gregorio Bigatti,&nbsp;Pablo E. Penchaszadeh","doi":"10.1111/ivb.12276","DOIUrl":"10.1111/ivb.12276","url":null,"abstract":"<p>Siphonariids are pulmonate gastropods inhabiting rocky intertidal habitats, and many studies have focused on these false limpets around the world. In the southern South Atlantic, studies on reproduction and development in species of <i>Siphonaria</i> are scarce. We studied the embryonic development and egg masses of <i>Siphonaria lateralis</i> at its northernmost distribution in Atlantic Patagonia<i>.</i> In <i>S. lateralis</i>, as in most species of <i>Siphonaria</i>, individuals spawn benthic egg masses that strongly attach to intertidal rocky substrata. A single spherical egg that measures ~120 µm develops inside the egg capsule of <i>S. lateralis</i>. Considering the relatively small egg size, and reports from previous studies, the developmental modality of <i>S. lateralis</i> might be expected to include a planktotrophic larval phase. However, we found that hatchlings emerged as 1-mm crawling juveniles, probably owing to the presence of intracapsular fluid, which may provide the energetic requirements for direct development. The embryonic size changed little from the egg to veliger stages, and then increased rapidly until the hatchling stage. We compared development in <i>S. lateralis</i> with development in the sympatric <i>Siphonaria lessonii</i>, in which egg size was reported to be ~80 µm and hatching occurs as planktotrophic veliger larvae. In these two species, spawn and early intracapsular developmental modes are remarkably different; these differences represent contrasting ways to survive in the harsh and physically stressful intertidal Patagonian coasts.</p>","PeriodicalId":54923,"journal":{"name":"Invertebrate Biology","volume":"139 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/ivb.12276","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44247541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolutionary derivation of the American lobster cardiovascular system: an hypothesis based on morphological and physiological evidence","authors":"M. J. Cavey, J. Wilkens, T. Yazawa","doi":"10.11575/PRISM/35102","DOIUrl":"https://doi.org/10.11575/PRISM/35102","url":null,"abstract":"The cardiovascular system of the American lobster includes a large muscular heart that pumps blood into seven arteries, each of which ramifies extensively. Portions of the system may be viewed as relatively primitive, while others are highly derived. We have confirmed earlier findings that the sternal artery is not a single vessel, but a paired structure. The sternal artery and its partner closely resemble the medial branches of the segmental lateral vessels from the dorsal abdominal artery in anterior segments of the abdomen, and they may be homologous. We report that the walls of the dorsal abdominal artery contain blocks of striated muscle cells and that the artery can be induced to contract in response to electrical stimulation or perfusion with proctolin. These observations provide the basis for an attempt to trace the evolution of the heart and arteries from that of primitive malacostracans to its state of development in lobsters. Additional key words: Crustacea, Homarus americanus, evolution, heart, dorsal abdominal artery, sternal artery We present here anatomical and physiological evidence supporting the hypothesis that the cardiovascular system in adult decapod crustaceans, as illustrated for Homarus americanus (e.g., McLaughlin 1983), is derived, by migration and regional specialization, from the evolutionarily primitive plan of a dorsal, longitudinal, tubular, muscular heart with a pair of ostia in each segment running from the head to the telson (Siewing 1963; Hessler et al. 1982). It has been postulated, based on the Cephalocarida, that crustacean ancestors displayed strong serial homology in body plan (Sanders 1955), possibly arising from annelid ancestral antecedants such as an extended nauplius-like larva (Hessler et al. 1982). The Cephalocarida and Branchiopoda (Anostraca, fairy shrimps) are closest to this prototype. This primitive plan is still the general plan in stomatopods (Siewing 1963; McLaughlin 1980). In the ancestral plan, the heart tube lies immediately dorsal to the gut and extends the entire length of the body. The heart tube supplies hemolymph to a short non-muscular anterior median artery to the brain, to some form of serially homologous segmental lateral arterial supply in each body segment, and to an unpaired posterior artery to the telson. The segmental a Author with whom to correspond. lateral arteries are short and do not branch extensively. Paired ostia admit returning hemolymph to the heart tube in each segment. In adults of H. americanus, the single-chambered heart is suspended in the pericardial sinus in the dorsal thorax by several pairs of alary ligaments (Lochhead 1950, pp. 428-431; McLaughlin 1980, pp. 138-141). These elastic ligaments are stretched during systole, and they expand the heart during diastole. During diastole, the heart passively fills with hemolymph from the pericardial sinus through three pairs of muscular,","PeriodicalId":54923,"journal":{"name":"Invertebrate Biology","volume":"53 1","pages":"30"},"PeriodicalIF":1.2,"publicationDate":"1997-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64322770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}