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1.
Hamulonema gen. nov. is proposed for Teladorsagia hamata and Ostertagia kenyensis in the ostertagiine nematode fauna found in artiodactyl hosts from Africa. Monomorphic species representing this genus are characterized by a bilaterally symmetrical and parallel synlophe in males and females, a 2-2-1 bursal formula, an accessory bursal membrane that is strongly cuticularized and reduced, a strongly reduced dorsal lobe and ray, and robust spicules with a simple, weakly pointed, ventral process, and curved, hooklike dorsal process. Species referred to Hamulonema nov. gen. are immediately distinguished from those of Camelostrongylus, Longistrongylus, Marshallagia, Orloffia, Ostertagia, and Pseudomarshallagia in which the bursal formula is 2-1-2 in males. Hamulonema nov. gen. is distinguished from those genera having a 2-2-1 bursa, including Africanastrongylus, Cervicaprastrongylus, Hyostrongylus, Mazamastrongylus, Sarwaria, Spiculopteragia, and Teladorsagia by the structure of the synlophe, bursa, genital cone, "0" and "7" papillae, dorsal lobe, and spicules in specific instances. In the global fauna, 4 of 14 ostertagiine genera are endemic to Africa. African genera may represent morphologically divergent and discrete or historically isolated lineages reflecting a pattern of geographic and host colonization as a driver for diversification since the Miocene.  相似文献   

2.
Among genera of the ostertagiine nematodes, structural attributes of Spiculopteragia caballeroi are consistent with criteria that diagnose the genus Sarwaria. Specifically, the following characters are compatible with referral to this genus: (1) species characterized by monomorphic males; (2) tapering lateral synlophe in the cervical zone; (3) minuscule, thornlike cervical papillae; (4) length of Ray "4" < Ray "5"; (5) relatively thick or robust Ray "4"; (6) a substantially reduced dorsal lobe and dorsal ray that are disposed or curved ventrally relative to Rays "8"; and (7) a broad, laterally inflated dorsal lobe. Consequently, we propose Sarwaria caballeroi n. comb., and we provide further validation for the genus Sarwaria. Additionally, we propose that the ostertagiines are represented by 12 valid genera, including those characterized by a bursal formula of 2-2-1 (Cervicaprastrongylus, Hyostrongylus, Mazamastrongylus, Spiculopteragia, and Teladorsagia in addition to Sarwaria), and those in which the lateral rays describe a 2-1-2 pattern (Camelostrongylus, Longistrongylus, Marshallagia, Orloffia, Ostertagia, and Pseudomarshallagia).  相似文献   

3.
Discovery of the ostertagiine nematode Teladorsagia boreoarcticus n. sp. in muskoxen, Ovibos moschatus, from the central Canadian Arctic highlights the paucity of knowledge about the genealogical and numerical diversity of nematode faunas characteristic of artiodactyls at high latitudes across the Holarctic. Teladorsagia boreoarcticus is a dimorphic cryptic species distinguished from Teladorsagia circumcincta/Teladorsagia trifurcata in domestic sheep by a 13% divergence in the ND4 region of mitochondrial DNA, constant differences in the synlophe, and significantly longer esophageal valve, spicules, gubernaculum, and bursa. Teladorsagia boreoarcticus represents an archaic component of the North American fauna and may have a Holarctic distribution in muskoxen and caribou. Recognition of T. boreoarcticus in muskoxen, in part, corroborates hypotheses for the existence of a cryptic species complex of Teladorsagia spp. among Caprinae and Cervidae at high latitudes and indicates the importance of climatological determinants during the late Tertiary and Pleistocene on diversification of the fauna. Also reinforced is the concept of the North American fauna as a mosaic of endemic and introduced species. Discovery of a previously unrecognized species of Teladorsagia has additional implications and clearly indicates that (1) our knowledge is incomplete relative to potentially pathogenic nematodes that could be exchanged among domestic and wild caprines; (2) we do not have sufficient knowledge of the fauna to understand the ecological control mechanisms (limitations) on dissemination and host range; and (3) an understanding of historical and geographical influences on the genealogical diversity and distribution of nematode faunas in domestic and wild ruminants is requisite to define the interface between agricultural and natural ecosystems across the Holarctic.  相似文献   

4.
Fleas of the Caucasus belong to 155 species of 40 genera, constituting 17% and 43% of the species and generic composition of the Palaearctic fauna, respectively. The Caucasian fauna includes 23 endemic species but no endemic genera or subgenera. In the number of species, the Caucasian fauna is similar to that of the Mediterranean Subregion and is significantly poorer than the faunas of the Euro-Siberian (by 2.2 times) and Irano-Turanian (by 1.7 times) Subregions. Based on taxonomic diversity, we can propose a hypothesis on the West and East Palaearctic sources of the Caucasian fauna. The West Palaearctic source has determined the distribution of pulicomorph fleas of the families Pulicidae and Coptopsyllidae from Africa, on the one hand, and of fleas of the genera Ctenopthalmus and Palaeopsylla from Europe, on the other hand. Fleas of the Holarctic genera, such as Ceratophyllus and Megabothris, entered the Caucasus by the north Asian route; fleas of the genera Neopsylla, Rhadinopsylla, and Hystrichopsylla migrated to the Caucasus from east and central Asia by the south Asian route, through Middle and Western Asia.  相似文献   

5.
A brief general characteristic and review of distribution of the subfamily Ceutorhynchinae over zoogeographical realms are given, with an emphasis on the distribution within the Holarctic and Palaearctic. The potential of exploiting landscapes of all natural zones of the Holarctic by a low-rank taxon is exemplified by the Holarctic Ceutorhynchus cochleariae (Gyll.) species-group comprising ca. 20 species evenly distributed between the Palaearctic and Nearctic. Although neighboring with the powerful centers of tropical biota, the Holarctic fauna of the subfamily Ceutorhynchinae is formed mostly of endemic and subendemic genera which are especially abundant in the Palaearctic. This region possesses the most diversified generic and species composition of the fauna consisting of predominantly endemic and subendemic genera (in the Mediterranean and Saharo-Gobian regions, also of the highly diversified tribe Oxyonychini) up to its southern border. The existence of characteristic transitional faunas in the zones of contact of the Holarctic fauna with the faunas of the tropical regions in East Asia and Mexico is shown. These transitional faunas include a considerable number of endemic taxa of the genus and species groups. A conspicuous feature of the Palaearctic ceutorhynchine fauna is the rather numerous complex of the upland and high-latitude species.  相似文献   

6.
A brachiopod fauna including 19 species of 17 genera from an exotic block in the Indus–Tsangpo suture zone in southern Tibet is described and illustrated. The brachiopod fauna is dominated by Martinia elegans and two new taxa: Jinomarginifera lhazeensis gen. et sp. nov. and Zhejiangospirifer giganteus sp. nov. The fauna is closely comparable with those from the middle and upper parts of the Wargal Formation and the Chhidru Formation in the Salt Range of Pakistan, the Chitichun Limestone in southern Tibet, and the Basleo area of West Timor, and these correlations suggest a Wuchiapingian age. The fauna exhibits substantial links with both peri–Gondwanan and Cathaysian faunas, which may imply that it is a seamount biota originally located in the southern margin of the Neotethys during the Late Permian, and was later (in the early Cenozoic) displaced and became sandwiched into younger marine deposits in the collision process between India and Eurasia.  相似文献   

7.
When studying Late Jurassic-Early Cretaceous radiolarians from the Nordvik section (Arctic Siberia), unique morphotypes of multicyrtoid nassellarians with many horns in the apical part of the shell, which continue the rays A, V, 2l, D, and 2L of the cephalic spicule, were recorded. These morphotypes are assigned to a new family, Echinocampidae fam. nov., including three new genera (Echinocampe gen. nov., Nordvikella gen. nov., and Arctocapsula gen. nov.) and eight new species. The family Echinocampidae was probably restricted to high latitudes and belonged to the boreal fauna of the terminal Jurassic and the basal Cretaceous.  相似文献   

8.
The synlophes of Ostertagia mossi Dikmans, 1931 and O. dikmansi Becklund & Walker, 1968 were found to be identical supporting recognition of these as the major and minor morphotypes, respectively, of a putative species pair within the Ostertagiinae. The cervical synlophe included three narrowly spaced, continuous, parallel ridges laterally and three parallel but more widely spaced ridges in the dorsal and ventral fields (Type II and Type A patterns, respectively). The disposition of the synlophe in conjunction with a long oesophageo-intestinal valve, and attributes of the genital cone and spicules are characteristics shared among other Ostertagia spp. from cervids in the Holarctic region that allow recognition of a species group morphologically distinct from the Ostertagiinae of domestic ruminants. The morphological similarity of O. mossi/O. dikmansi, O. leptospicularis Assadov, 1953/O. kolchida Popova, 1937 and O. gruehneri Skrjabin, 1929/O. arctica Mitzkewitsch, 1929 is substantial, but these species can be differentiated by small but constant differences in the synlophe and genital complex of males; females cannot be easily distinguished. The morphological similarity of this cryptic complex of species and their relatively restricted distribution among cervids suggests a coevolutionary history for hosts and parasites in the Holarctic region.  相似文献   

9.
Abstract: Bulk sampling of upper Campanian to lower–middle Maastrichtian coastal and lagoonal deposits in five sections of the Tremp Formation in the south‐central Pyrenees yielded numerous neoselachian teeth. The fauna comprises nine taxa of which three species and one genus are new: Hemiscyllium sp., Lamniformes indet., Paratrygonorrhina amblysoda gen. et sp. nov., Coupatezia trempina sp. nov., Coupatezia sp., Coupatezia? sp., Rhombodus ibericus sp. nov. and Igdabatis indicus. The neoselachian fauna is dominated by small nectobenthic rays. This composition resembles assemblages known from the marine Upper Cretaceous, but differs from nearby localities of the Basque‐Cantabrian region and continental selachian associations of the French Pyrenees. The results indicate that Rhombodus might not be a reliable biostratigraphic marker for the Maastrichtian. The faunal composition suggests a shallow trans‐Tethyan connection between Eurasia and India at the end of the Cretaceous Period.  相似文献   

10.
Giant deer or megacerines (tribe Megacerini, family Cervidae, order Artiodactyla) dwelt in Eurasia from the Late Miocene to Holocene and in Africa in the Late Pleistocene. Based on comparative morphological data and morphofunctional analysis, morphogenetic and ecogenetic trends in this group are improved. Classification, taxonomy, phylogeny, and geographical and stratigraphical ranges of megacerines are revised.  相似文献   

11.
Summary Nudora omercooperi sp. nov. is described from a fresh-water spring below high tide mark at Claytons Rocks, South Africa. It is characterized by a massive gubernaculum and the form of various modifications of the cuticle.
Résumé Nudora omercooperi sp. nov. est une forme plus originale avec des déformations caractéristiques de la cuticule et un gubernaculum très massif.


Department of Zoology, British Museum (Natural History).  相似文献   

12.
The distribution of distances between cuticular ridges was studied in six genera of ostertagiines. It was well fitted by a Gaussian function of the position of the inter-ridges on both the dorsal and ventral regions of the synlophe. The three parameters of the fitted function were very similar in individuals of the same species but of different origin or morphs, similar in different species of the same genus, but often differed between genera. Further comparative evaluation of the inter-ridge distance is required in order to assess its value as a taxonomic criterion.  相似文献   

13.
Study on rugose coral fauna of the Sifengya Formation(early Telyehian)and Daluzhai Formation (mid-late Telychian)in Daguan area,northeast Yunnan Province,China was carded out.Rugose coral fauna of the Sifengya Formation included 18 genera and 34 species,while Daluzhai Formation with nine genera,ten species.We described rugose coral fauna(12 genera,19 species)including one new genus and five new species,i.e.Protoketophyllum daguanense gen.et sp.nov..Crassilasma huanggexiense sp.nov.,Pseudophaulactis heae sp.nov.,P.convolutus sp.nov.,and Shensiphyllum minor sp.nov..The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation were analyzed.Particularly,mgose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper Yangtze region and improve the sequences of early Silurian(Llandovery)mgose coral assemblages in Yangtze region.It is therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch.  相似文献   

14.
The insect fauna of the Lower Permian Tyulkino locality in the Perm Region of Russia is considered. New members of the orders Trichoptera and Eoblattida are described. Members of the primitive family Microptysmatidae (suborder Protomeropina) are typical of the Lower and Middle Permian deposits of Eurasia and are represented by the two genera: Microptysmella Kukalová-Peck et Willmann, 1990 and Kamopanorpa Martynov, 1928. Kamopanorpa tyulkiana sp. nov. and K. tamarae sp. nov. (Trichoptera, Microptysmatidae) and Parakhosara kamica sp. nov. (Eoblattida, Megakhosaridae) are described.  相似文献   

15.
Two new species of trichostrongylid parasites of a mountain gorilla in Uganda are described. Paralibyostrongylus kalinae n. sp. is characterised by a short dorsal ray, a dorsal oesophageal tooth and two median longitudinal ridges in the vulvar region. The species is more closely related to leporid parasites than to P. hebrenicutus, another species known from the gorilla. A “transfuge” phenomenon, i.e. transfer to a new host without speciation is suggested. Hyostrongylus kigeziensis n. sp. has several specific morphological characteristics and in particular a synlophe with many strong ridges, rays 4 and 5 divergent at the apex, and the dorsal ray with two branches. Hyostrongylus appears to be an Ethiopian genus which has radiated in many archaic mammals. With the technical collaboration of Mrs. N. Caillaud and Mr R. Tchesprakoff. With the technical collaboration of Mrs. N. Caillaud and Mr R. Tchesprakoff.  相似文献   

16.
李新江  印象初 《昆虫学报》2009,52(10):1139-1145
本文对欧亚大陆裸蝗亚科(Conophyminae)进行了系统的分类研究, 将其分为4个族, 其中包括3个新族, 即贝氏蝗族(Bienkoini tribe nov.)、庚蝗族(Genimenini tribe nov.)和普乐氏蝗族 (Plotnikovini tribe nov.), 记述了一新属--原无翅蝗属Eozubovskya gen. nov., 并附已知4族25属的检索表。将该亚科中原有3个具翅的属(Khayyamia Kocak, 1981, Conophymacris Willemse, 1933 和Zagrosia Descamps, 1967)移出, 归入秃蝗亚科(Podisminae)。  相似文献   

17.
The rich fauna of Late Devonian (Late Frasnian) siliceous sponges from the Holy Cross Mountains, Poland is composed of 15 species and 11 genera. Both astylospongid demosponges (lithistids) and hexactinosan hexactinellids are present. The following new genera and/or species are proposed: D regulara Rigby and Pisera sp. nov., Jazwicella media Rigby and Pisera gen. et sp. nov., Astyloscyphia irregularia Rigby and Pisera gen. et sp. nov., A. turbinata Rigby and Pisera gen. et sp. nov., Astylotuba modica Rigby and Pisera gen. et sp. nov., Paleoregulara cupula Rigby and Pisera gen. et sp. nov., Paleoramospongia bifurcata Rigby and Pisera gen. et sp. nov., Cordiospongia conica Rigby and Pisera gen. et sp. nov., Paleocraticularia elongata Rigby and Pisera gen. et sp. nov., P gigantia Rigby and Pisera gen. et sp. nov., Polonospongiadevonica Rigby and Pisera gen. et sp. nov., P fistulata Rigby and Pisera gen. et sp. nov., Urnospongia modica Rigby and Pisera gen. et sp. nov., and Conicospongia annulata Rigby and Pisera gen. et sp. nov. The investigated fauna contains the youngest astylospongiids known and the oldest well-preserved, and most diversified Palaeozoic hexactinosans. The sponge fauna constituted a significant element of a brachiopod-coral-sponge assemblage that inhabited a deep slope of the local Dyminy Reef structure, during its final phase of growth, in a clearly hemipelagic setting. This fauna is limited to the intrashelf depression within an incipiently drowned carbonate platform.  相似文献   

18.
19.
The Eocene (Bartonian) marls of the La Guixa Member and Gurb Member, Vic Marls Formation (Ebro Basin, Catalonia, Spain), contain a very rich and diversified siliceous sponge fauna. The fauna is dominated by hexactinellids; lithistids and other demosponges are rare. It consists of 16 species representing 16 genera. Eleven new species and two new genera are proposed for these sponges: Reguantella cavernosa nov. gen. nov. sp., Regadrella concinna nov. sp. (both Hexactinellida, Lyssacinosa), Eurete clava nov. sp., Pleuroguettardia iberica nov. sp., Aphrocallistes almeriae nov. sp., Hexactinella informis nov. sp. (all Hexactinellida, Hexactinosa), Brachiolites munterensis nov. sp., Centrosia viquensis nov. sp., Callicylix eocenicus nov. sp., Rhizocheton robustus nov. sp. (all Hexactinellida, Lychniscosa), Propetrosia pristina nov. gen. nov. sp. (Demospongia, Haplosclerida). Some genera of sponges in this fauna are still extant, but, in general, the predominant ones are very close in morphology, and, without doubt, closely related to the Late Cretaceous sponges. This fauna also differs considerably, in terms of composition, from most other described faunas of Tertiary sponges from the Mediterranean region, which are dominated by lithistid sponges. Lithistid sponges are rare in this investigated assemblage, which seems most similar to an as yet undescribed Eocene fauna from Italy. There is ecological differentiation in the proportions of particular sponges in various outcrops and/or stratigraphical levels that is clearly associated with water-depth-related controlling factor(s): Munter, Tona and Sta. Cecilia represent the deepest facies, Gurb is intermediate, and St. Roc and Vespella are the most shallow. The exact bathymetric position of the sponge fauna is difficult to estimate, but it seems that 100 m (but probably 200 m and more in the case of the deepest parts) of water depth may be inferred for this facies.  相似文献   

20.
Study on rugose coral fauna of the Sifengya Formation (early Telychian) and Daluzhai Formation (mid-late Telychian) in Daguan area, northeast Yunnan Province, China was carried out. Rugose coral fauna of the Sifengya Formation included 18 genera and 34 species, while Daluzhai Formation with nine genera, ten species. We described rugose coral fauna (12 genera, 19 species) including one new genus and five new species, i.e. Protoketophyllum daguanense gen. et sp. nov., Crassilasma huanggexiense sp. nov., Pseudophaulactis heae sp. nov., P. convolutus sp. nov., and Shensiphyllum minor sp. nov. The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation were analyzed. Particularly, rugose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper Yangtze region and improve the sequences of early Silurian (Llandovery) rugose coral assemblages in Yangtze region. It is therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch. __________ Translated from Acta Palaeontologica Sinica, 2005, 44(2): 229–246 [译自: 古生物学报, 2005, 44(2): 229–246]  相似文献   

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