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1.
Ostracods have discontinuous development, marked by ecdyses, and determinate growth. Ontogenetic studies have suggested a pattern of nine postembryonic stages (eight juvenile phases and the adult) for the main freshwater ostracod superfamilies Cypridoidea, Cytheroidea and Darwinuloidea. However, cases of a supposed extra moult in the adult stage have been proposed for some ostracod species, which would amount to 10 postembryonic growth stages. One such example is Elpidium bromeliarum Müller, 1880, a cytheroidean that inhabits tank-bromeliads. The present study is aimed at investigating the ontogenetic development of E. bromeliarum using width and length measurements, as well as carapace and appendage morphology in order to test the existing hypothesis of an additional growth stage in adults of this species. Our results revealed nine postembryonic growth stages (eight juvenile and the adult), with sexual dimorphism beginning its expression in the last juvenile stage. Thus, the ontogenetic development of E. bromeliarum agrees with the overall pattern observed for podocopid ostracods and the hypothesis of 10 postembryonic growth stages was not corroborated. We argue that the inability to differentiate juveniles from adults, or different species from one another, may have misled to the assumption of an additional moult in E. bromeliarum.  相似文献   

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《Journal of Natural History》2012,46(35-36):2199-2206
The oribatid mite genus Arphthicarus Niedba?a, 1994 (Phthiracaridae) is reported in China for the first time. Two new species of Arphthicarus are described: Arphthicarus baculus sp. nov. from Hunan Province, and Arphthicarus spiniformis sp. nov. from Guangxi Province.

http://zoobank.org/urn:lsid:zoobank.org:pub:A1729EB7-2C99-4BF6-94EB-229E2A743D84.  相似文献   

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A new introduced species, Otala punctata (Müller, 1774) and new records in Chile for Cornu aspersum (Müller, 1774) and Deroceras laeve (Müller, 1774) are documented based on surveys carried out in northern and central areas of the country. The presence and distribution of these alien species are complemented with a comprehensive compilation of all 34 non-indigenous species of marine, freshwater and terrestrial Mollusca in Chile; until 1999, only 16 alien species were known in Chile. Most of these alien species are found exclusively in transformed habitats, few exist in natural environments. The mechanism of introduction for the majority of these non-indigenous species is unknown; however, horticultural development, urban and suburban transformation of original natural habitats, and the aquarium trade are the most likely pathways of introduction. The highest threat of alien species is direct competition and predation of native molluscs, especially the small native land gastropods. Education and continuous field surveys are vital to detect and prevent their propagation as well as to avoid introduction of additional alien taxa.  相似文献   

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《Journal of Natural History》2012,46(10):1417-1431
Enchytraeid surveys were made in China, mainly along the Changjiang (Yangtze) River Basin, during the period 1991–1999. Among the findings, four terrestrial species of Marionina are new to science and well illustrate the taxonomic complexity of the genus as currently defined. Marionina sinica sp. n. is characterized by a specific chaetal distribution, the marionine pattern of the dorsal blood vessel, and elongate, fusiform, spermathecal ectal ducts. Marionina sacculata sp. n. is distinguished by the possession of a pair of pouch-like oesophageal appendages in IV, the lack of lateral chaetae in VII–XI, a marionine pattern of the dorsal blood vessel, and short spermathecal ectal ducts gradually expanding into spherical ampullae. Both M. sinica and M. sacculata have minute bodies (2–3 mm long in vivo) and lack spermathecal accessory glands. The former species shows its closest aYnities with the European M. brendae Rota, 1995, whereas the latter is closest to the German M. hoVbaueri Möller, 1971, for which an amended diagnosis is provided. Marionina seminuda sp. n. has only ventral chaetal bundles, distributed from III onwards and bisetose. It is similar to the Holarctic M. subterranea (Knöllner, 1935) in lacking entirely the lateral chaetae and in having the brain incised posteriorly, the dorsal vessel bifurcating behind the pharynx, and coelomocytes containing opaque granules, but diVers from it in having the longest chaetae in preclitellar segments and gland cells distributed all over the spermathecal ectal ducts. Marionina righiana sp. n. is diagnosed by the location of the head pore on the prostomium, the absence of lateral chaetae from VIII (VII or IX) onwards, the possession of free spermathecae extending backwards through one to four segments, the brain deeply incised posteriorly, the lumbricilline pattern of the dorsal blood vessel, and the opacity of coelomocytes in vivo. Prior to this study, members of the genus so atypical as M. righiana with respect to the position of the head pore and the structure of the spermathecae were known only from South American soils. Until the taxonomy of Marionina has been more thoroughly assessed and revised, the assignment of the four species to this large assemblage should be regarded as tentative.  相似文献   

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《Journal of Natural History》2012,46(5-8):401-417
Four species of Caligus, with two new species, are reported from five species of marine fishes of Taiwan. They are: Caligus arii Bassett‐Smith, 1898 Bassett‐Smith, P. W. 1898. Further new parasitic copepods found on fish in the Indo‐tropical region.. Annals and Magazine of Natural History (Series 7), 2: 7798. [Taylor & Francis Online] [Google Scholar] on the body surface of Trichiurus lepturus Linnaeus, Caligus dasyaticus Rangnekar, 1957 Rangnekar, M. P. 1957. Caligus dasyaticus sp. nov. and Caligus dussumieri sp. nov., (Copepoda) parasitic on Bombay fishes.. Journal of the University of Bombay, 25: 1622.  [Google Scholar] on the body surface of Dasyatis navarrae (Steindachner), Caligus dactylus n. sp. on the gill filaments of Dactyloptera peterseni (Nyström), and Caligus lutjani n. sp. in the oral/gill cavities of Lutjanus argentimaculaltus (Forsskål) and Lutjanus bohar (Forsskål). Both C. arii and C. dasyaticus are reported for the first time from Taiwan. Caligus dactylus differs from its congeners by the possession of the following combination of features: large myxal process on the maxilliped; a pair of parallel tines on the sternal furca with truncate tip; simple elements (without accessory process) at the tip of leg 1 exopod; and an armature formula of I‐0; I,III on leg 4. Caligus lutjani is distinguished by carrying a two‐segmented abdomen; a pair of diverged tines on the sternal furca with acute tip; an accessory process on the middle two of the terminal four elements on the exopod of leg 1; and a bipectinate, spiniform process on the exopod of leg 4 at the insertion of each of the five outer spines.  相似文献   

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《Journal of Natural History》2012,46(37-40):2425-2451
A century ago Bürger described the species Drepanophorus valdiviae from a single specimen taken from 155 m off the southern tip of Africa by the research vessel Valdivia during the German Deep Sea Expedition. Stiasny-Wijnhoff in 1923 Stiasny-Wijnhoff, G. 1923. On Brinkmann's system of the Nemertea Enopla and Siboganemertes weberi n. g. n. sp. Q J Microsc Sci., 67: 627669.  [Google Scholar] transferred this species along with Amphiporus stannii (sensu Bürger 1895 Bürger, O. 1895. Die Nemertinen des Golfes von Neapel und der angrenzenden Meeres-Abschnitte. Fauna und Flora des Golfes von Neapel, 22: 1743.  [Google Scholar]) to a new genus Valdivianemertes but did not mention a family affiliation. In 1993 Crandall transferred this genus to the family Cratenemertidae. During the Spanish Antarctic Expedition BENTART 2003, carried out on board the RV Hespérides, we found one specimen identified with certainty as Valdivianemertes valdiviae, at 602 m depth in the Bellingshausen Sea (Antarctica). As there is no extant holotype, we here redescribe this species from this new specimen and designate it the neotype of this species; photomicrographs of the different regions of the body and the proboscis structure are provided for the first time.  相似文献   

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《Journal of Natural History》2012,46(17):1381-1393
Anyphops Benoit is a heterogeneous genus with 62 known species restricted to the Afrotropical region. It is split into four species groups using the number of ventral spine pairs on tibiae I–II. The lycosiformis species group (?=?B‐B1 species group of Lawrence) is characterized by four ventral pairs of spines and includes Anyphops lycosiformis (Lawrence), A. natalensis (Lawrence) and A. parvulus (Pocock). In this paper, I revise this species group and include here A. mumai Corronca, A. lawrencei (Roewer) and two new species: Anyphops ngome n. sp. and A. lucia n. sp. from South Africa. Drawings of the female and male genitalia and some somatic characters are given, in some cases for the first time. A key for the lycosiformis species group and a map showing the distribution of each species are provided.  相似文献   

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《Journal of Natural History》2012,46(11):1359-1358
Increasing oil-exploration activity and associated ecological surveying west of the Shetlands is leading to the discovery of many poorly known or undescribed tanaidaceans. Three species of the typhlotanaid genus Paratyphlotanais Kudinova-Pasternak and Pasternak, 1978 Kudinova-Pasternak R. K Pasternak F. A 1978 Deep sea Tanaidacea collected from the Caribbean Sea and Puerto Rico trench during the 16th cruise of RV ‘Akademik Kurchatov’ and the resemblance between the fauna of deep-sea Tanaidacea of the Caribbean region and the Pacific Trudy Instituta Okeanologiii. Akademiya Nauk SSSR, 113, 115–135 (in Russian)  [Google Scholar] have been recorded from shelf and bathyal depths between Iceland, the Faroe Islands and the western margin of the British Isles. Two, P. gracilipes (Hansen) and P. microcheles (G. O. Sars), formerly belonging to the genus Typhlotanais, are redescribed and a new species is described. A key to their identification is included. Inhabiting largely discrete zoogeographic areas, these species help define regional macrofaunal associations.  相似文献   

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