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1.
We present a systematic list of the echinoderms from Gulf of Mexico's Mexican waters based on specimens of the Colecci6n Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Aut6noma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. This list reveals an important echinoderm biodiversity present in the Gulf of Mexico, where five of the six echinoderm classes are represented. A total of 209 echinoderm species is recorded, distributed in 129 genera, 63 families and 25 orders. 31 new records for the Gulf of Mexico are presented: Asteroidea (16), Ophiuroidea (nine), Echinoidea (one) and Holothuroidea (five).  相似文献   

2.
A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A total of 193 echinoderm species is recorded, distributed in 108 genera, 51 families and 19 orders. 12 new records for the Gulf of California are presented: Asteroidea (four), Ophiuroidea (three) and Holothuroidea (five).  相似文献   

3.
A systematic list of the echinoderms of the Mexican Caribbean based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. This list reveals an important echinoderm biodiversity in the Mexican Caribbean, where five of the six echinoderm classes are represented. A total of 178 echinoderm species is recorded, distributed in 113 genera, 51 families and 22 orders. 30 new records for the Mexican Caribbean are presents: Crínoidea (three), Asteroidea (two), Ophiuroidea (eleven), Echinoidea (one), Holothuroidea (thirteen).  相似文献   

4.
This paper examines published information and gray literature about taxonomy and ecology of echinoderm species of the Colombian Pacific Coast. Unpublished collection data of specimens kept in the Marine Sciences Museum of the University of Valle are also considered. Sixty-six species are found in coastal ecosystems and shallow bottoms of ten geographical, coastal and insular localities of the Pacific coast of Colombia. Main habitats having echinoderms are: rocky cliffs and shores, coral reefs, sand beaches, mud substrates, mangroves, and shallow bottoms of mud, sand, gravel and rocks. Regular Echinoidea and Asteroidea are the most diverse and abundant groups, mainly in subtidal rocky shallow bottoms and coral reefs. Ophiuroidea are abundant below rocky boulders. Irregular Echinoidea are abundant on sand beaches. The relatively high number of species shows that this geographical area presents a high diversity of echinoderms compared with other tropical shallow and littoral zones of the world. Rocky substrates and coral reefs are the ecosystems with the highest numbers of echinoderm species and individuals. A conservation status assessment is difficult because the lack of periodical sampling and few data about deep zones. In general, the species reported in the last 25 years, have not experimented important changes in their populations, although in some specific places, populations may decrease because human activities in coastal areas increase sedimentation rates change some rocky substrates to mud or sand.  相似文献   

5.
The enigmatic echinoderms attracted few adherents in the 19th century, but this Yorkshireman almost-literally gave his life to them. He amassed the finest collection in private hands, which has been on display in the Exeter Museum since 1910.  相似文献   

6.
The problem of the unknown relationship between the radial body form of echinoderms and the bilateral body form of their relatives and ancestor is approached here by applying a hypothetical ancestral gastrulation pattern to the echinoderm body plan. The result is a prediction of the homologue in echinoderms of the bilateral plane of bilateral forms. The predicted plane is identified in the adult rudiment of the echinoid Holopneustes purpurescens as the plane through the oral anlagen, the future anus and future madreporite. It is also, therefore, the plane through the classically described Carpenter axis. Based on this identification, other bilateral homologues are proposed and a model of the bilateral echinoderm ancestor is constructed. The bilateral homologues are potentially testable by the techniques of molecular embryology.  相似文献   

7.
There has been no previous systematic statewide study of mosquitoes in Mississippi. This survey, resulting in the collection of over 400,000 specimens, was conducted by the authors from 2003 to 2007 throughout much of the state using CO2‐baited CDC light traps and larval dipping. In addition, a health department contract mosquito surveillance technician collected several thousand specimens from the state from 2001 to 2003. Lastly, specimens housed at the Mississippi State University Entomological Museum, obtained from previous surveys, were included as vouchers for species occurring in the state. The collection records and literature show 60 species as occurring or having occurred in Mississippi. Voucher specimens representing 57 of the 60 species discussed are deposited in the Mississippi Entomological Museum or in the U.S. National Museum of Natural History (USNM), Washington, D.C.  相似文献   

8.
The active evolutionary lives of echinoderm larvae   总被引:4,自引:0,他引:4  
Raff RA  Byrne M 《Heredity》2006,97(3):244-252
Echinoderms represent a researchable subset of a dynamic larval evolutionary cosmos. Evolution of echinoderm larvae has taken place over widely varying time scales from the origins of larvae of living classes in the early Palaeozoic, approximately 500 million years ago, to recent, rapid and large-scale changes that have occurred within living genera within a span of less than a million years to a few million years. It is these recent evolutionary events that offer a window into processes of larval evolution operating at a micro-evolutionary level of evolution of discrete developmental mechanisms. We review the evolution of the diverse larval forms of living echinoderms to outline the origins of echinoderm larval forms, their diversity among living echinoderms, molecular clocks and rates of larval evolution, and finally current studies on the roles of developmental regulatory mechanisms in the rapid and radical evolutionary changes observed between closely related congeneric species.  相似文献   

9.
In China, there are about 37 species of vipers belonging to 12 genera in the family Viperidae. In the Herpetological Museum of the Chengdu Institute of Biology(CIB), Chinese Academy of Sciences, the type specimens of snakes represent seven species in four genera. As a series of reports on the type specimens of Amphibians and Reptilies deposited in the Herpetological Museum of CIB, this paper focuses on the venomous snake family Viperidae in the collections at this Museum.  相似文献   

10.
About 40 type specimens of archostematan beetles from the Jurassic, Lower Cretaceous, and Paleogene of England, named by P. Brodie, J.O. Westwood, C. Giebel, A. Handlirsch, F. Zeuner, P. Whalley, and R. Crowson and stored in the Paleontological Department of the Natural History Museum (London) are redescribed. Nine genera and 11 species are recognized, three genera are assigned to Archostemata for the first time. One new species, Tersus crowsoni (Schizophoridae), is described.  相似文献   

11.
The Invertebrate section of the Museum of Zoology QCAZ at the Pontifical Catholic University of Ecuador in Quito maintains nearly two million curated specimens, and comprises Ecuador’s largest collection of native taxa. We review 1902 type specimens from 6 subspecies and 320 species in 121 genera and 42 families, currently kept in the Museum. The list includes 116 holotypes, 10 allotypes, 1774 paratypes and 2 neoparatypes. The collection of type specimens is particularly strong in the Coleoptera (family Carabidae and Staphylinidae) and Hymenoptera. However, other insect orders such as Diptera and Lepidoptera and non-insect arthropods such as Acari, Aranea and Scorpiones, are moderately represented in the collection. This report provides original data from labels of every type specimen record. An analysis of the geographic distribution of type localities showed that collection sites are clustered geographically with most of them found towards the northern region of Ecuador, in Pichincha, Cotopaxi and Napo provinces. Sites are mainly located in highly accessible areas near highways and towns. Localities with a high number of type species include the cloud forest reserve Bosque Integral Otonga and Parque Nacional Yasuní in the Amazon rainforest near PUCE’s Yasuní Scientific Station. Type localities are not well represented in the Ecuadorian National System of Protected Areas. Future fieldwork should include localities in the southern region of Ecuador but also target less accessible areas not located near highways or towns. We discuss the value of the collection as a source of information for conservation and biodiversity policies in Ecuador.  相似文献   

12.
DNA barcode reference libraries linked to voucher specimens create new opportunities for high-throughput identification and taxonomic re-evaluations. This study provides a DNA barcode library for about 45% of the recognized species of Canadian Hemiptera, and the publically available R workflow used for its generation. The current library is based on the analysis of 20,851 specimens including 1849 species belonging to 628 genera and 64 families. These individuals were assigned to 1867 Barcode Index Numbers (BINs), sequence clusters that often coincide with species recognized through prior taxonomy. Museum collections were a key source for identified specimens, but we also employed high-throughput collection methods that generated large numbers of unidentified specimens. Many of these specimens represented novel BINs that were subsequently identified by taxonomists, adding barcode coverage for additional species. Our analyses based on both approaches includes 94 species not listed in the most recent Canadian checklist, representing a potential 3% increase in the fauna. We discuss the development of our workflow in the context of prior DNA barcode library construction projects, emphasizing the importance of delineating a set of reference specimens to aid investigations in cases of nomenclatural and DNA barcode discordance. The identification for each specimen in the reference set can be annotated on the Barcode of Life Data System (BOLD), allowing experts to highlight questionable identifications; annotations can be added by any registered user of BOLD, and instructions for this are provided.  相似文献   

13.
Sulfated fucans are among the most widely studied of all the sulfated polysaccharides of non-mammalian origin that exhibit biological activities in mammalian systems. Examples of these polysaccharides extracted from echinoderms have simple structures, composed of oligosaccharide repeating units within which the residues differ by specific patterns of sulfation among different species. In contrast the algal fucans may have some regular repeating structure but are clearly more heterogeneous when compared with the echinoderm fucans. The structures of the sulfated fucans from brown algae also vary from species to species. We compared the anticoagulant activity of the regular and repetitive fucans from echinoderms with that of the more heterogeneous fucans from three species of brown algae. Our results indicate that different structural features determine not only the anticoagulant potency of the sulfated fucans but also the mechanism by which they exert this activity. Thus, the branched fucans from brown algae are direct inhibitors of thrombin, whereas the linear fucans from echinoderms require the presence of antithrombin or heparin cofactor II for inhibition of thrombin, as reported for mammalian glycosaminoglycans. The linear sulfated fucans from echinoderms have an anticoagulant action resembling that of mammalian dermatan sulfate and a modest action through antithrombin. A single difference of one sulfate ester per tetrasaccharide repeating unit modifies the anticoagulant activity of the polysaccharide markedly. Possibly the spatial arrangements of sulfate esters in the repeating tetrasaccharide unit of the echinoderm fucan mimics the site in dermatan sulfate with high affinity for heparin cofactor II.  相似文献   

14.
本文报道中国缘脊叶蝉亚科肠槽叶蝉属Drabescus 3个新种,并列出了本属中国分布种名录。模式标本分别保存于西北农林科技大学昆虫博物馆(NWSUAF)、中国科学院动物研究所标本馆(IZAS)、美国自然博物馆(USNM)和英国伦敦自然博物馆(BMNH)。  相似文献   

15.
The external features of a shortened, apluteal development (lacking a pluteus larva) are described. Some features are unusual for echinoids. The large egg is distinctively marked by dark and pale coloured yolk. The sperm entry point is marked by a dark yolk spot and the first cleavage plane in most embryos is through the meridian on which the sperm entry point lies. Dark yolk in the animal hemisphere segregates largely to one blastomere in the two-cell embryo and pale yolk segregates to the other as a result of yolk movements during the first cell cycle. Progeny of the pale-yolk blastomere form adult oral structures and progeny of the dark-yolk blastomere form adult aboral structures. There is no feeding planktonic pluteus larva. The gastrula develops into a demersal vestibula larva with bilateral symmetry. The plane of symmetry is coincident with the Carpenter axis that defines a plane of symmetry through the madreporite in adult echinoderms. The coincidence shows that the anterior ambulacrum is vegetal with respect to egg polarity and the interradius originating at the madreporite is animal. The bilateral symmetry of the vestibula offers insight into the origin of radial symmetry in echinoderms and the body plan of an echinoderm ancestor.  相似文献   

16.
Among 381 specimens of Cambrian stalked echinoderms from eastern Guizhou, China examined, several slabs ( n  = 19) contain either dumbbell-shaped or v-shaped echinoderm clusters. Four slabs of Globoeocrinus globules Zhao, Parsley & Peng, 2008 from the middle-upper part (Cambrian Series 3 portion) of the Kaili Formation are prepared to reveal the attachment sites. Articulated gogiid echinoderms are reported to be attached to both sides of inarticulate (organophosphatic) brachiopods; thus, allowing me to interpret that the larvae of these gogiids were capable of attaching to live benthic brachiopods. This study documents the one of the earliest examples of echinoderms employing secondary tiering, which elevates an organism higher into the benthic boundary layer. Many of the gogiid echinoderm pairs attached to a live brachiopod are similar in size, indicating they were from a single larval spatfall.  相似文献   

17.
Life history evolution and comparative developmental biology of echinoderms   总被引:3,自引:1,他引:2  
Evolutionary biologists studying life history variation have used echinoderms in experimental, laboratory, and field studies of life history evolution. This focus on echinoderms grew originally from the tradition of comparative embryology, in which echinoderms were central. The tools for obtaining and manipulating echinoderm gametes and larvae were taken directly from comparative embryological research. In addition, the comparative embryologists employed a diverse array of echinoderms, not a few model species, and this diversity has led to a broad understanding of the development, function, and evolution of echinoderm larvae. As a result, this branch of life history evolution has deep roots in comparative developmental biology of echinoderms. Here two main aspects of this relationship are reviewed. The first is a broad range of studies of fertilization biology, dispersal, population genetics, functional morphology, and asexual reproduction in which developmental biologists might take a keen interest because of the historical origins of this research in echinoderm comparative embryology. The second is a similarly broad variety of topics in life history research in which evolutionary biologists require techniques or data from developmental biology in order to make progress on understanding patterns of life history variation among echinoderm species and higher taxa. Both sets of topics provide opportunities for interaction and collaboration.  相似文献   

18.
The feeding deterrent effects of echinoderm body-wall tissues and ethanolic extracts containing mid-polarity compounds were evaluated utilizing generalist fish and crabs as model predators. The body-wall tissues of the echinoderms examined ranged 10-fold from 0.9–9.4 mm in thickness, and four and a half-fold in level of mineralization (17.8–82.7% ash content). Holothuroids had the thickest body-wall tissues and contained the lowest levels of mineralization in their body-walls. Crinoids and ophiuroids had high levels of mineralization in their arms. Asteroid body-wall tissues varied the most in thickness and ash content (0.9–3.9 mm in thickness and 29.2–55.5% in ash content). Body-wall tissues of 19 species of echinoderms were tested for their feeding deterrent properties against the marine fishes Lagodon rhomboides (Linnaeus) and Cyprinodon variegatus (Lacepede), as well as the decapod crustacean Libinia emarginata (Leach). Equivalent sized pieces of fresh body-wall tissue of 16 species of echinoderms caused observable feeding deterrence responses in at least two of the three model predators. There was no significant correlation between body-wall thickness or percent ash and its palatability to any of the three model predators. Agar pellets containing ethanolic body-wall extracts of 12 of 18 echinoderm species caused observable feeding deterrence responses in the fish L. rhomboides. In similar experiments with the arrow crab Stenorhyncus seticornis (Herbst), using carrageenan fish-meal blocks as food models, no differences in consumption of control fish-meal and experimental body-wall extract blocks were detected. Our findings indicate that invertebrate and vertebrate predators may respond quite differently to echinoderm body-wall extracts.  相似文献   

19.
The species composition and patterns of distribution of echinoderms from the upper sublittoral zone to depth of 30 m in the southern and middle of Kola Bay in the Barents Sea were studied. In total, five species of starfishes, four species of brittle stars, three species of sea urchins and one species of holothurians were recorded. From the beginning of 20th century, under the impact of climate change and anthropogenic effect, the number of echinoderm species in the surveyed area decreased by two times, and the fauna has a more boreal character against the background of the domination of boreal-arctic species. The occurrence, population density and biomass of echinoderms, especially of common species, were several times less in the middle bend of the bay than in the southern one. The causes of this phenomenon have been discussed. The quantitative data (frequency of occurrence, number and biomass) for most of the species of echinoderms living in Kola Bay are given for the first time.  相似文献   

20.
中国叶蚜亚科分类学研究(同翅目,蚜科)   总被引:3,自引:3,他引:0  
中国叶蚜亚科Phyllaphidinae已知4属,迪叶蚜属Diphyllaphis Takahashi,1960,楠叶蚜属Machilaphis Takahashi,1960,叶蚜属Phyllaphis Koch,1856和群斑蚜属Thelazacallis Zhang,2000;4个种,栎迪叶蚜Diphyllaphis quercus (Takahashi,1960),楠叶蚜Machilaphis machili(Takahashi,1928),山毛榉叶蚜Phyllaphis fagi(Linnacus,1767)和毛茛群斑蚜Thelazacallis ranunculicola Qiao et Zhang,2000.其中叶蚜属和山毛榉叶蚜为中国新纪录.文中提供了分属检索表,各属提供了鉴别特征,所有分类单元提供了文献引证、寄主植物、地理分布和检视标本的记录.新纪录种有详细的形态记述和特征图.研究标本保存在中国科学院动物研究所动物标本馆.  相似文献   

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