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1.
The present paper reports 10 species of trematodae parasites belongingto the family Bucephalidae Poche,1907 collected from fishes in PoyangLake of Jiangxi,among them two are new species,one new records.The new species are briefly characterized as follow:  相似文献   

2.
A new species of mermithid nematodes was collected from theinfected larvae of Agrotis ipsilon in Anqing,Anhui in 1984-1985.It is identif-ied as new species of the genus Hexamermis.Hexamermis agrotis sp.nov.  相似文献   

3.
In this paper one new genus and one new species of fossil ommatid, Odontomma trachylaena gen. et sp. nov., is described and illustrated from the Late Jurassic or Early Cretaceous Yixian Formation of western Liaoning, China. Based on wide epipleural space of elytron with several rows of cells, the new taxa is attributed to tribe Brochocoleini of Ommatidae and compared with genus Brochocoleus. Due to the fact that most other Chinese Mesozoic ommatids are not complete, the complete preservation of the new specimens reported here enabled us to determine the characteristics of the body of these ancient ommatid. Moreover, based on the well-preserved individual of this new genus, we may suppose the affinities of the new species with extant and extinct groups.  相似文献   

4.
A new species of Gobiconodon is found from the Yixian Formation of western Liaonlng, China. The new taxa,G zofiae sp. nov., has a confluent opening for branches Ⅱand Ⅲ of the trigeminal nerve on the anterior lamina of the petrosal. G zofiae sp. nov. is similar to Repenomamus in having an ossified Meckel‘s cartilage connecting the lower jaws and ear region. The new species, with enlarged I^1/I1, posteriorly located infraorbital foramen and four mental foramina,distinctly differs from the other species of Gobiconodon. The new material indicates that Gobiconodon has four, not five,upper molariforms. The presence of Gobiconodon in Jchol Biota makes it possible to correlate Jehol Biota with faunas in eastern Asia and North America, and suggests the age of the Yixian Formation to be Early Cretaceous.  相似文献   

5.
A new genus and species of eutriconodont mammal, Chaoyangodens lii gen. et sp. nov., from the Dawangzhangzi bed of Yixian Formation, Lingyuan, Lia- oning, is reported. The new species has a tooth formula I5- C1-P1-M3/i4-cl-pl-m4, unique among eutriconodonts in having only one premolar in lower and upper jaws, respectively, and a distinctive diastema between the canine and the premolar. Its simple incisors and reduced premolars show a mosaic combination of primitive and derived fea- tures. This new taxon adds to the diverse group of Jehol eutriconodonts. Among the known species from at least three horizons, there seems no evolutionary trend in mor- phology that is recognizable, except for that larger species are all from the Lujiatun bed of the Yixian Fro. A thorough and systematic analysis involving all the Jehol eu- triconodonts is needed to understand their phylogenetic relationships.  相似文献   

6.
A new species,Helicoprion jingmenense sp. nov.,from the Lower Permian Qixia Formation of Hubei Province,China,is described based on a nearly complete symphyseal tooth spiral preserved as part and counterpart. The specimen is a large elliptical symphyseal tooth spiral with 41/3 volutions,with cutting blade being relatively wide,and its width being greater than the height after 31/2 volution,middle portion being higher than the cutting blade,narrowed base being short. There is a distinct space not covered by enameloid in two adjacent tooth crowns in the outermost two volutions; the height of the compound root is moderate,and the ventral groove is about 1/10 of the same tooth crown. In com-parison with other known Helicoprion species of the world,the new species resembles H. ferrieri and H. bessonowi. However,it can be easily distinguished from H. ferrieri by the wider cutting blade,the shorter narrowed base and lower compound root,and also from H. bessonowi by its more narrowed compound root and less than 39 tooth crowns per volution. Helicoprion jingmenense sp. nov. is obvi-ously different from helicoprionid species previously found in China in general shape,size and his-tology. However,it is very difficult to identify their relationships because of the fragmentary nature of holotypes of the latter. Because the new specimen is the first record of Helicoprion and the most com-plete fossil dentition of helicoprionids from China,the new species is of significance for biostratigra-phy and paleobiogeography.  相似文献   

7.
Climate change poses major new challenges to biodiversity conservation. Distribution ranges of species have been proven to be affected by climate anomalies. Detecting the extent of protected species response to climate change can help formulate flexible conservation strategies to overcome the changing climate. Using species distribution modeling and high resolution climate data, we simulated current distribution patterns of 233 protected plants in China. Those patterns were then projected into future suitable habitats for each species under nine climate change scenarios, with no migration or full migration hypotheses. Under the most extreme climate change scenario (CGCM-B2a), we evaluated species extinction risks. Sixteen percent of protected plants are expected to lose more than 30 % of their current ranges. By calculating areal shifts, hotspots for emigrants, immigrants, and persistent species were identified under climate change. Flexible conservation strategies were addressed for those regions. Those strategies strongly depend on the migration types of species and sensitivity of the hotspots to changing climate. In hotspots for emigrants, the main conservation strategy is ex situ protection; protected species from these regions should be stored in seed banks or botanical gardens. For hotspots of immigrants, enough space should be maintained for new species, and some measures are necessary to assist dispersal. For hotspots of persistent species, more natural reserves are needed. We highlight related fields that can help conserve protected species in the future, such as conserving the soil seed bank and understanding of the effects of migration ability and interactions between protected species.  相似文献   

8.
9.
A new genus and three new species of fossil Palaeontinidae, Papilioncossus conchatus sp. nov., P. giganteus sp. nov. and P. pteroideus sp. nov., are described. All of them were collected from Middle Jurassic Jiulongshan Formation in Inner Mongolia, China. Based on distal part of forewing broader and longer than basal and Sc usually with branches, the new taxa are attributed to Palaeontinidae of Homoptera and compared with genus Pseudocossus. A key to species of Papilioncossus gen. nov. is provided. All type specimens are deposited in the Capital Normal University.  相似文献   

10.
A new genus and three new species of fossil Palaeontinidae, Papilioncossus conchatus sp. nov., P. giganteus sp. nov. and P. pteroideus sp. nov., are described. All of them were collected from Middle Jurassic Jiulongshan Formation in Inner Mongolia, China. Based on distal part of forewing broader and longer than basal and Sc usually with branches, the new taxa are attributed to Palaeontinidae of Homoptera and compared with genus Pseudocossus. A key to species of Papilioncossus gen. nov. is provided. All type specimens are deposited in the Capital Normal University.  相似文献   

11.
First discovery of Promimomys (Arvicolidae) in East Asia   总被引:2,自引:0,他引:2  
Promimomys asiaticus sp. nov., the first known species of the genus in East Asia, is described. The material was collected from the early Pliocene cave deposit in Dajushah Hill, Huainan, Anhui Province. Promimomys was first found in Europe and considered as the ancestor of the family Arvicolidae. The new species from China is distinct from the type species, P. cor, and other known species in its thicker enamel of uniform thickness, simple anterior loop of ml, and blunt, salient angles. It is more primitive than other known species in Europe and North America and also more primitive than Mimomys bilikeensis of early Pliocene of Inner Mongolia. It is thus the earliest and the most primitive arvicolid rodent known. The discovery of Promimomys asiaticus sp. nov. is significant to the study on the origin and the phylogeny of arvicolids, and to the discussion of the intercontinental dispersal events of arvicolids.  相似文献   

12.
Palissya,a little-known reproductive organ with a long history,is recorded from China and Asia for the first time.A new species,Palissya hunanensis(sp.nov.) ,is described from the Upper Triassic Rhaetican strata of the Zixing coal field of Hunan Province.The ovulate cone has a compound shoot system that consists of a main axis and many helically-arranged axillary structures re-ferred to as female dwarf shoots,each of which is subtended by a bract.Despite a superficial similarity,P.hunanensis differs from the typical species P.sphenolepis(Braun) Nathorst in a number of subtle but consistent features:the cone is much smaller and narrower,the bracts are much thinner,there are fewer pairs of cup-like seed scales,and the seed scales are adaxially attached to a thick axis rather than to bracts.These traits are all distinctly different from other species of the genus.Moreover,SEM obser-vation of the new species reveals morphological features of the seed scales and seeds and details of the female dwarf shoot;sig-nificantly increases our knowledge of Palissya;and provides new evidence that it is a conifer.Palissya is related to the Lower Permian Lebowskia,a voltzian conifer bearing ovuliferous structures similar to the bract plus dwarf-shoot organization of Palis-sya.Palissya-type conifers probably grew in specialized marine-continent habitats,unlike most other extant and extinct conifers that grow in drier upland environments.  相似文献   

13.
14.
The Tianyuan Cave is the only human fossil-bearing site containing rich mammalian fossils found in the last decades near Zhoukoudian. Up to now more than 34 specimens of the human body have been recovered, and the mammalian fossils can be put into 29 species. Cervids dominate the fauna, and carnivores are very rare. Based on the primary examination, the human fossils can be attributed to the species Homo sapiens. All the mammalian fossils, except one between tooth of Crocuta belong to the species that still exist today. But some of them are the first records in fossil form north of the Yellow River, such as Arctonyx and Capricornis. Based on the mammalian fauna study, it seems that the Tianyuan Cave can be correlated with the Upper Cave.Sixty-three percent of the species of the mammalian fauna from the Tianyuan Cave are also present in the Upper Cave.The characters of the deposits also share some similarities between the Tianyuan Cave and the Upper Cave; both of them are mainly composed of breccia without cement. The dating using the U-series method on deer tooth samples indicates that the geological age of the new site is around 25 thousand years B.P. This is the first discovery of human sites outside the core area of the Peking Man Site at Zhoukoudian,which throws new light onto this world famous site complex.  相似文献   

15.
The Lower and Middle Jurassic insects are rather poorly known from Northwest China. Here we restudy Parahagla lamina Lin, 1982 and transfer it from “Parahagla” to Aboilus Martynov, 1925. On the basis of the female forewing, we described two new species of the EarlyMiddle Jurassic, Aboilus tuzigouensis sp. nov. caome from Badaowan Foramtion at Tuzigou, Kelamayi, Xinjiang, Northwest China and A. jiyuanensis sp. nov. from Ma’ao Group, Jiyuan, Henan Province, Central China. The differences of the new materials from the other known species and their systematic positions are also discussed.  相似文献   

16.
The Lower and Middle Jurassic insects are rather poorly known from Northwest China. Here we restudy Parahagla lamina Lin, 1982 and transfer it from “Parahagla” to Aboilus Martynov, 1925. On the basis of the female forewing, we described two new species of the EarlyMiddle Jurassic, Aboilus tuzigouensis sp. nov. caome from Badaowan Foramtion at Tuzigou, Kelamayi, Xinjiang, Northwest China and A. jiyuanensis sp. nov. from Ma’ao Group, Jiyuan, Henan Province, Central China. The differences of the new materials from the other known species and their systematic positions are also discussed.  相似文献   

17.
This paper presents 5 new species of graptolite we collected in S. Anhui, the main members of them pertaining to family Phyllograptidae. The specimens of Azygograptus and Sinograptidae Mu are obtained at the first time ( 1958 ) in southeastern China.  相似文献   

18.
A new reduced chemical kinetic model of 1-pentene is developed based on a detailed chemical kinetic model of 1-pentene at high temperature(194 species and 1266 reactions).By means of sensitivity and flow rate analyses,32 important reactions are determined,on the basis of which a reduced chemical kinetic model consisting 50 species and 251 reactions is proposed through addition of other important species and reactions.The results show that the simulated cylinder pressure and temperature calculated using the reduced model agree well with those from the detailed model.The reduced model requires less computing time than the detailed model,which enables coupled computation of the chemical kinetic model with computational fluid dynamics.  相似文献   

19.
A new species of the elaterid genus Cryptocoelus Dolin and Nel, 2002 from the Late Jurassic to Early Cretaceous Yixian Formation in the western Liaoning, China is described. Diagnosis of the genus is revised, and the systematic position of the genus is briefly discussed. Because the elaterids originated in the Early to Mid-Jurassic, this new material from the Late Jurassic-Early Cretaceous will enhance our understanding of the transition between ancient elaterids and extant ones, bridge the gap of cryptic relationships between the Mesozoic cupedids and elaterids, and expand our knowledge of their evolutionary history.  相似文献   

20.
The Yuanmou Basin of Yunnan Province is a hotspot for the research of early homind evolution and its environmental background.During the implementation of the Program“Research of the Origin and Evolution of Early Man and Its Environmental Baqckground” from 1998 to 2001,a huge quantity of hominoid and mammal fossils were collected.The present report systematically describes an Euprox robustus sp.nov.identified during the recent laboratory work on the collected material.Euprox is a group of earliest cervids with true antlers.The new species is the third one of the genus discovered in China.Judged by its morphologic characteristics,the new species feed on juicy and tender leaves of dicotyledon.It implies that the vegetation of its epoch in the Yuanmou Basin is a kind of southern subtropical evergreen forest and the climate is humid and temperate with evident seasonality.The latter is mostly influenced by the monsoon and secondly by the latitude.  相似文献   

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