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1.
A new species of the holopodid genus Cyathidium was found on rocks off Grande Comore in a depth of around 200 m. Based on external morphology of resting animals, the new species Cyathidium plantei sp. n is described, with emphasis on comparison to the only other extant species ( C. foresti ) as well as to the four extinct representatives of the genus. Concerning morphological characters, the new species is almost identical to the Cretaceous C. depressum . A cladistic analysis of the entire family, including the genus Holopus, shares a peculiar pattern of bending of the arms, which in principle is an apomorphic character of the family and in detail shows variations within the family. In addition, stratigraphic data are used for the determination of the evolutionary direction. This analysis reveals that the two recent species are closely related to each other, and to the fossil C. depressum . from which the entire family is probably derived.  相似文献   

2.
A new genus Simplicaris (Copepoda, Harpacticoida, Parastenocarididae) is established to accommodate two species collected from deep groundwater in Italy, S. lethaea sp. nov. and S. veneris (Cottarelli & Maiolini, 1980) comb. nov. Parastenocaris hippuris Hertzog, 1938 and P. aedes Hertzog, 1938 are ranked as incertae sedis within the genus. Members display complete absence of leg 5 in both sexes and an unusual elongation of the first exopodal segments of legs 1–4, in which exp-1 is distinctly longer than exp-2 or -3, or as long as exp-2 and -3 combined. As the systematic status of the family Parastenocarididae and of the type genus Parastenocaris is still in flux, a list of phylogenetically informative characters is proposed, along with a discussion of their various states in representative members of the family. The genus Parastenocaris sensu stricto is redefined to comprise only the brevipes -group. The remaining members of the genus are considered Parastenocaris sensu lato pending a thorough revision of the family.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 417−436.  相似文献   

3.
A new family of the order Rhabdomesida, Medvedkellidae fam. nov., is described. This family consists of a new genus, Medvedkella gen. nov., comprising three species transferred from the genus Rhombopora Meek, 1872: the type species M. riasanensis (Schulga-Nesterenko, 1955), M. diaphragmata (Schulga-Nesterenko, 1955), and M. mariae (Dunaeva, 1961). The morphogenesis of the first two species is studied. For the first time axial zooecia are revealed in the suborder Golgdfussitrypina, which existed in parallel with the suborder Rhabdomesina of the order Rhabdomesida. A hypothesis that the new family evolved from the subfamily Nicklesoporinae Gorjunova, 1985 of the family Goldfussitrypidae, 1985 is proposed. Some questions of the ecological adaptation of these bryozoans in the Late Carboniferous marine basin of the East European Platform are discussed.  相似文献   

4.
根据形态和分子系统发育证据,描述采自我国西南的新属和新种毛离褶伞Tricholyophyllum brunneum。与离褶伞科其他属不同,该新属的菌盖表皮为毛皮状,菌柄表皮为不连续的毛皮状,有褶缘囊状体,担孢子长椭圆形至圆柱形。  相似文献   

5.
6.
A genus and species of Antarctic benthic hydroids new to science, Mixoscyphus antarcticus gen. nov., sp. nov., is described and figured. Its systematic position amongst allied genera of the family Sertulariidae is discussed. The studied material originates from the South Shetland Islands area (West Antarctica), which was collected by several Spanish and US Antarctic expeditions. Mixoscyphus gen. nov. currently represents the only complete endemic genus of Antarctic benthic hydrozoans. A discussion of other genera of benthic hydroids that are largely endemic to the Antarctic is also provided.  相似文献   

7.
Mangin  K. L. 《Hydrobiologia》1991,216(1):443-451
Samuraia tabularasa, the samurai hydroid, a previously unreported genus and species of athecate hydrozoan, family Hydrocorynidae, is described, based upon field and laboratory observations. Colonies live attached to rocky substrates in the middle of the intertidal zone in the northern and central Gulf of California, Mexico. The principal characters that allow this species to be referred to a new genus are associated with its mode of sexual reproduction by eumedusoids that can remain attached to the colony, or be released as ephemeral, rudimentary structures. This is in contrast to the feeding, free medusae produced by the two species of the other genus, Hydrocoryne, in the family Hydrocorynidae.  相似文献   

8.
Free-swimming definitive males of two species of Tantulocarida (Crustacea), Arcticotantulus pertzovi (Basipodellidae) and Microdajus tchesunovi (Microdajidae), were reared for the first time. Their morphology and ultrastructure were studied using scanning electron and light microscopy. A detailed analysis of the morphological characters of all currently described species revealed several features typical for most known male tantulocaridans, such as the presence of eight aesthetascs, seven pairs of multifid sensilla on the carapace, paired brush setae on the protopods of the thoracopods, and three furcal setae. The monophyly of the families Microdajidae and Doryphallophoridae is corroborated, while the families Deoterthridae and Basipodellidae are more likely paraphyletic.  相似文献   

9.
Soil from a roadside ditch at Lake Waccamaw, North Carolina, was tested for cyst-forming free-living amoebae, and water from the same ditch was tested for fecal coliform bacteria. Soil samples incubated at room temperature (21-23° C) yielded Acanthamoeba polyphaga, Amoeba sp., Hyperamaeba sp., Mayorella penardi. Naegleria gruberi, Naegleria minor , and unidentified ciliates, testaceans and slime molds. Incubation at 37-39° C yielded Acanthamoeba jacobsi, Platyamoeba schaefferi , and a new amoeba to be described herein. Fecal contamination of the ditch was confirmed by a direct membrane filtration technique that yielded a mean of 1,410 + 134 bacteria/ ml. The new amoeba is assigned to the class Heterolobosea Page & Blanton, 1985 on the basis of promitotic nuclear division, and a flagellated stage with a cytostome as seen in the genus Tetramitus. Amoebae studied in hanging drop preparations were flattened and irregular as described for the genus Stachyamoeba in the family Gruberellidae but changed to a lobose cylindrical form as described for species of Vahlkampfia in the family Vahlkampfiidae. A new genus and species, Learamoeba waccamawensis , is proposed for the amoeba described herein.  相似文献   

10.
11.
Morphology, ontogeny and the molecular phylogeny of Agolohymena aspidocauda nov. gen., nov. spec., a new freshwater tetrahymenid ciliate from Idaho, U.S.A, are described. The ontogeny and histophagous mode of nutrition are similar to those of Deltopylum rhabdoides Fauré-Fremiet and Mugard, 1946. The new genus is placed with Deltopylum in the resurrected family Deltopylidae Song and Wilbert, 1989. We emend the diagnostic features of the family to include division by polytomy, right and left somatic kineties extending into the preoral suture, crook-shaped or sigmoid adoral membranelles 1 and 2, markedly reduced adoral membranelle 3 and a tetrahymenid silverline pattern. The main diagnostic features of the new genus are a disc-shaped caudal ciliary array and formation of two types of resting cysts, one smooth and the other bearing tangled tubular or cylindrical lepidosomes. Nuclear small subunit ribosomal RNA gene and mitochondrial cytochrome oxidase subunit 1 gene sequences place the new genus basal within the order Tetrahymenida, well separated from members of the family Tetrahymenidae (Lambornella and Tetrahymena) and also from other tetrahymenids (Colpidium, Dexiostoma, Glaucoma). The genetic divergences between this species and other genera in Tetrahymenida are large enough to suggest placement of the new genus in a separate family. This corroborates the morphological data, since the elaborate caudal ciliary array and the lepidosome-covered resting cyst of this species are not found in other Tetrahymenidae.  相似文献   

12.
Abstract

A replacement name, Turneriella is proposed for an Australian moth genus, the monotypic genus Amblyzancla Turner, 1939 in the family Yponomeutidae (Lepidoptera, Yponomeutoidea).  相似文献   

13.
1. During late spring 1993–1995, the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) sampled 490 wadeable streams in the mid‐Atlantic Highlands (MAH) of the U.S. for a variety of physical, chemical and biological indicators of environmental condition. We used the resulting data set to evaluate the importance of differing levels of macroinvertebrate taxonomic resolution in bioassessments by comparing the ability of family versus genus to detect differences among sites classified by type and magnitude of human impact and by stream size. We divided the MAH into two physiographic regions: the Appalachian Plateau where mine drainage (MD) and acidic deposition are major stressors, and the Ridge and Valley where nutrient enrichment is a major stressor. Stream sites were classified into three or four impact classes based on water chemistry and habitat. We used stream order (first to third Strahler order) in each region as a measure of stream size. Ordination, 2 × 2 chi‐square and biotic metrics were used to compare the ability of family and genus to detect differences among both stressor and size classes. 2. With one notable exception, there were only a small number of different genera per family (interquartile range = 1–4). Family Chironomidae, however, contained 123 different genera. As a result, significant information loss occurred when this group was only classified to family. The family Chironomidae did not discriminate among the predefined classes but many chironomid genera did: by chi‐square analysis, 10 and 28 chironomid genera were significant in discriminating MD and nutrient impacts, respectively. 3. Family and genus data were similar in their ability to distinguish among the coarse impacts (e.g. most severe versus least severe impact classes) for all cases. Though genus data in many cases distinguished the subtler differences (e.g. mixed/moderate impacts versus high or low impacts) better than family, differences in significance levels between family and genus analyses were relatively minor. However, genus data detected differences among stream orders in ordination analyses that were not revealed at the family level. In the ordinations, both family and genus levels of analysis responded to similar suites of environmental variables. 4. Our results suggest that identification to the family level is sufficient for many bioassessment purposes. However, identifications to genus do provide more information in genera‐rich families like Chironomidae. Genus or finer levels of identification are important for investigating natural history, stream ecology, biodiversity and indicator species. Decisions about the taxonomic level of identification need to be study specific and depend on available resources (cost) and study objectives.  相似文献   

14.
A crocodilian jaw fragment from the Jurassicof Thailand is referred to a new species of the genus SunosuchusYoung,, 1948, S. thailandicus.. The genus Sunosuchus,, which is interpreted here as belonging to the family Goniopholididae (Mesosuchia),, was previously known only from the continental Jurassic of north-central China. The occurrence of this freshwater crocodilian in the Khorat Group of Thailand provides evidence that, whatever its previous palaeogeographical history may have been, by Jurassic times South-East Asia was part of Laurasia.  相似文献   

15.
Spumochlamys iliensis n. g., n. sp. was isolated from a mineral pond in an arid, semi-desert region in Kazakhstan (Central Asia). This amoeba is covered with a plate-shaped, flexible organic spongious test. The thin membranous margin of this test extends ventrally to surround a flexible ventral aperture. In its morphological features and behaviour this amoeba is very similar to Microchlamys patella (Claparède and Lachmann, 1859) Cockerell, 1911, but differs from this species and from M. sylvatica Golemansky, Skarlato and Todorov, 1987 in the lack of an additional membrane separating the cell body from the test, a feature that can only be detected using electron microscopy. The presence of this membrane is considered to be a principal characteristic of the genus Microchlamys and family Microchlamyiidae; however, this conclusion was reached from the study of only two species. The data presented show a higher diversity of Microchlamys-like testate amoebae; we therefore suggest that the described species should be included in the family Microchlamyiidae with emendation of its diagnosis, but that a separate genus within this family should be established to accommodate it.  相似文献   

16.
Up to the present, the genus Leptostichaeus has been considered as belonging to subfamily Lumpeninae. A series of characters was analyzed for family and subfamily diagnostics within the group Stichaeidae. It was found that, in combination of all examined characters, the genus Leptostichaeus is either similar to Azygopterus or occupies an intermediate position between the latter and other members of the family Stichaeidae. The genus Leptostichaeus is transferred into the group Azygopterinae, which is revalidated as a subfamily within the family Stichaeidae.  相似文献   

17.
《Mycoscience》2014,55(2):144-148
A new genus Verrucocephalum is proposed for a fungus which was found from bat dung collected in a limestone cave. The type species, V. latericorvinisporum has darkly pigmented spores and aseptic hyphae that branch and capture nematodes by means of appressoria. These morphological characteristics match the definition for the family Helicocephalidaceae (Zoopagales, Zoopagomycotina). The genus can be distinguished from three previously known genera in the family by its broad-based tapering sporophores with darkly pigmented verrucose spores born on short lateral branchlets. The branchlets may be homologous to the papillae seen in genus Rhopalomyces.  相似文献   

18.
金道超 《昆虫学报》1999,42(3):311-314
记述了安徽黄山的喜沼螨科Limnocharidae, 喜沼螨亚科Limnocharinae的一新属侧喜沼螨属、一新种黄山侧喜沼螨Laterolimnochares huangshanensis gen. Nov.,sp. Nov.,该科及亚科的中国区系过去仅由Uchida于1941年简录过东北之一种。文中给出了喜沼螨亚科的属检索表;详述了新种腺毛分布体位。  相似文献   

19.
A new family. Tridentellidae, is established for the genus Tridentella. T. vitae sp. nov. is described and figured and T. saxicola is recorded with figures. The phylogenetic position of the family is discussed, and notes provided on the natural history of the genus.  相似文献   

20.
In a preliminary cladistic analysis of the bivalve family Cardiidae (Schneider 1992), members of the subfamilies Protocardiinae, Lahilliinae, and Laevicardiinae, plus the genus Nemocardium , were found to be the least derived taxa of cardiids. A cladistic analysis is undertaken of the genera and subgenera of these cardiid taxa, plus several Mesozoic taxa which have never been assigned to any subfamily. The Late Triassic Tulongocardium , which is placed in Tulongocardiinae subfam. n., is the sister taxon to all other cardiids. Protocardiinae is restricted to the genus Protocardia. Most other Mesozoic taxa which have been placed in the Protocardiinae are found to be members of the Lahilliinae. Nemocardium is placed in the Laevicardiinae. Incacardium, Pleuriocardia , and Dochmocardia form a monophyletic group, Pleuriocardiinae subfam. n. Pleuriocardiinae, Laevicardiinae, and the remaining members of the Cardiidae (herein informally termed "cucardiids") form a monophyletic group.  相似文献   

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