首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Fabien Knoll 《Geobios》2002,35(5):595
A new ornithischian skull from the Elliot Formation of southern Africa is described. The specimen is compared in detail with the fabrosaurid Lesothosaurus diagnosticus. It actually shares many characters with specimens of the syntypes of this species or specimens referred to it. It is nevertheless not identical to any of these specimens and it is, moreover, remarkably larger than them. The possibility of attributing this specimen to a so far undescribed ‘large fabrosaur’ from the same formation is discussed. It is concluded that the specimen in question in this paper, while being ascribable to the genus Lesothosaurus, cannot be determined to a specific level until the existence of two fabrosaurid species in the ‘Stormberg Group’ is demonstrated and their range of morphological and size variation is properly appraised.  相似文献   

2.
《Palaeoworld》2015,24(4):470-478
Two new species of flexible crinoids of the genus Cibolocrinus (Crinoidea, Flexibilia) from the Upper Carboniferous of the Moscow Region are described: C. kutasovi (Moscovian Stage, Podolskian Regional Substage) and C. gerassimovi (Gzhelian Stage, Dobryatinian Regional Substage). The first species, C. kutasovi, belongs to a group with low cone shaped cups that first appeared in the Moscow Basin and then spread to the Midcontinent of North America. In one specimen of C. gerassimovi the smallest infrabasal plate is situated in the A ray, which is not typical for flexible crinoids. A poorly preserved crown of Cibolocrinus sp. from the Upper Carboniferous (Gzhelian Stage) of the Darvaz Ridge (western Pamir, central Tajikistan) is also described. The described specimens of Cibolocrinus from the Moscow Region and the Darvaz Ridge are the first reliable specimens of this genus described from Europe and Asia.  相似文献   

3.
A proboscidean skull from Cheparawa, (Muruyur Formation, Kenya), differs markedly from those of Eurasian Choerolophodon (C. pentelici, C. dhokpathanensis). It is morphologically and metrically close to the holotype of Choerolophodon kisumuensis (MacInnes) a partial skull from Maboko, much of which has been reconstructed in plaster of Paris. The more complete remains of this species now available indicate that it should be placed in a genus separate from Choerolophodon. The new genus Afrochoerodon is erected for it. Choerolophodon ngorora from Ngorora and Fort Ternan (Kenya), Choerolophodon zaltaniensis from Gebel Zelten (Libya) and Choerolophodon chioticus from Chios, Greece, should be transferred to the genus Afrochoerodon. Late Miocene specimens from Nakali, Kenya are probably referrable to the genus Choerolophodon. Fossils from Burji-Soyama (Ethiopia) hitherto assigned to Choerolophodon sp. are excluded from the subfamily Choerolophodontinae.  相似文献   

4.
5.
J. M. Campbell 《ZooKeys》2014,(415):269-293
The species of the genus Charisius Champion, from Mexico and Central America are reviewed. The flightless genus Narses Champion, with one included species, N. subalatus Champion, is placed in synonymy with the genus Charisius. Four new species are described and illustrated, C. granulatus and C. punctatus (from Guatemala) and C. apterus and C. howdenorum (from Mexico). Charisius subalatus (Champion) is redescribed and illustrated. The species C. interstitialis Champion is placed in synonymy with C. zunilensis Champion. The genus is redescribed to include the four new species and N. subalatus. New distributional records are presented for all other species of the genus and a revised key is presented for identification of all the species of the genus.  相似文献   

6.
During the expedition “ANTARTIDA 9101”, organized by the Spanish Oceanographic Institute to the South Orkney Islands, four specimens of notaspidean gastropods were collected. Three of them have been identified as Bathyberthella antarctica Willan and Bertsch, 1987. However, one specimen, although externally similar to B. antarctica, had an internal anatomy exhibiting features that have enabled us to consider it to be a new genus and species. This new taxon is characterized by the presence of jaws without mandibular elements, and a vaginal gland that partially surrounds the distal region of the vaginal duct. In this paper the new genus and species is described. Additional anatomical data of the specimens of B. antarctica collected during the expedition are also included.  相似文献   

7.
There are a total of 16 fossil cercopithecid specimens, representing at least 10 individuals, from the Chiwondo Beds of northern Malawi. The majority of this material is derived from the Middle Pliocene Unit 3A, but one specimen is from the Early Pliocene Unit 2. This latter specimen is from a papionin of indeterminate genus similar in size to Parapapio ado and Pliopapio alemui. Among the specimens from Unit 3A, two species can be diagnosed: an indeterminate species of Theropithecus, and a species of Parapapio similar in dental size to P. broomi. Neither of the genera from Unit 3A are exclusive to either East Africa or South Africa. Their relative abundances, however, are more similar to Middle Pliocene South African sites where Parapapio is the most common primate genus, and Theropithecus is comparatively rare. This is in contrast to similarly-aged East African sites where Theropithecus is by far the most abundant genus.  相似文献   

8.
A total of five species the genus Orius are revised from the Korean Peninsula, containing four native species, O. minutus (Linnaeus 1758), O. sauteri (Poppius 1909), O. nagaii Yasunaga 1993 and O. strigicollis (Poppius 1914), and an introduced species for biological control, O. laevigatus Fieber 1860. Orius laticollis Reuter 1884, formally recorded in the Korean Peninsula, is deleted from the Korean fauna registry. The preparation of the macerated slide specimen was applied to this group for the first time, which is confirmed to be effective to identify the Orius species, especially the female specimens whose genital structures have been hardly observed in the traditional dissection method. Observing macerated specimens, new taxonomical characters are documented.  相似文献   

9.
Despite its wide, almost worldwide distribution, the mayfly genus Cloeon Leach, 1815 (Ephemeroptera: Baetidae) is restricted in the Western hemisphere to North America, where a single species is reported. In the Neotropics, except for some species wrongly attributed to the genus in the past, there are no records of Cloeon. Recently, however, specimens of true Cloeon were collected along the coast of Espírito Santo, Southeastern Brazil. In order to verify the hypothesis that this species was recently introduced to Brazil, our aim was to identify the species based on morphological and molecular characters and to confirm the presence of true representatives of the genus in the Neotropics. Our results revealed that the specimens found in Brazil belong to the Afrotropical species C. smaeleni Lestage, 1924. The identity of the species, its distribution, along with its previous absence in regularly sampled sites, is a clear sign that the specimens of C. smaeleni found in Espírito Santo are introduced, well established, and that the colonization took place very recently.  相似文献   

10.
New material attributed to the species Iasvia reticulata ZALESSKY, 1934 and to a new species in this genus is described from the Salagou Formation (Saxonian Group, Lodève basin). Preamble to the taxonomic section, the wing venation pattern of Orthoptera is discussed. The numerous described specimens yield decisive information about variability of wing venation within the genus, previously based on a single specimen from the Russian Permian. I. reticulata is the first species from the Lodève basin that is already known from another site. The biostratigraphic implications are discussed.  相似文献   

11.
《Geobios》2016,49(6):459-467
Traditionally, the lower boundary of the Emsian (Lower Devonian) has been defined as the base of the dehiscens Zone marked by the first entry of the conodont Polygnathus dehiscens. However, following taxonomic revision of P. dehiscens, the current practice is to use the first appearance of P. kitabicus to define the base of the Emsian. As a result, specimens previously identified as P. dehiscens from South China need to be thoroughly reviewed. Careful examination of the oral and aboral features of the platform reveal that most specimens previously described as P. dehiscens from nine sections in Guangxi and Yunnan actually refer to P. excavatus excavatus or P. excavatus ssp. 114. In the South China Block, widespread and massive deposition of Devonian carbonates began during the time of the excavatus Zone, whereas the kitabicus Zone is probably located in the underlying strata, which mainly comprise marine siliciclastic rocks. Thus, the precise level of the lower boundary of the Emsian in South China is still unknown.  相似文献   

12.
Rivera-Ortiz JA  Cano H  Marí F 《Peptides》2011,32(2):306-316
The venom of cone snails (ssp. Conus), a genus of predatory mollusks, is a vast source of bioactive peptides. Conus venom expression is complex, and venom composition can vary considerably depending upon the method of extraction and the species of cone snail in question. The injected venom from Conus ermineus, the only fish-hunting cone snail species that inhabits the Atlantic Ocean, was characterized using nanoNMR spectroscopy, MALDI-TOF mass spectrometry, RP-HPLC and nanoLC-ESI-MS. These methods allowed us to evaluate the variability of the venom within this species. Single specimens of C. ermineus show unchanged injected venom mass spectra and HPLC profiles over time. However, there was significant variability of the injected venom composition from specimen to specimen, in spite of their common biogeographic origin. Using nanoLC-ESI-MS, we determined that over 800 unique conopeptides are expressed by this reduced set of C. ermineus specimens. This number is considerably larger than previous estimates of the molecular repertoire available to cone snails to immobilize prey. These results support the idea of the existence of a complex regulatory mechanism to express specific venom peptides for injection into prey. These intraspecies differences can be a result of a combination of genetic and environmental factors. The differential expression of venom components represents a neurochemical paradigm that warrants further investigation.  相似文献   

13.
14.
15.
The occurrence of Paleozoic gastropods attached to echinoderms has been recognized for nearly 170 years. Specimens have been illustrated from each of the geologic periods from the Ordovician to Permian. We illustrate two occurrences of Permian platycrinitid camerate crinoids from West Timor, Platycrinites s.s. wachsmuthi (Wanner) and Neoplatycrinus dilatatus Wanner, that have the platyceratid attached on the tegmen on the former and along the radial summit on the latter. Both platyceratids barely cover the anal opening and suppress the development of the arms of at least one ray. The D ray arms are suppressed on Platycrinites s.s. wachsmuthi, whereas the development of the C ray arms and perhaps the most adjacent arms of the D and B rays are suppressed on Neoplatycrinus dilatatus. An additional specimen of Neoplatycrinus major retains the impressed conch outline of a formerly attached platyceratid on the tegmen. This is the first report of a platyceratid/Neoplatycrinus association. The West Timor occurrences are among the youngest known of the platyceratid/platycrinitid association before the End-Permian extinction of the camerates. In addition, an abnormal four-rayed theca of Platycrinites s.s. wachsmuthi is described.  相似文献   

16.
17.
Ant species found as syninclusions with aphids in Rovno and Saxonian ambers are listed for the first time. In a collection of 143 pieces of Rovno amber with worker ants, aphids were found in only one syninclusion with Ctenobethylus goepperti (Mayr). In a collection of Saxonian amber, 53 aphids of the genus Germaraphis were found in 152 amber pieces with ant workers; five syninclusions with aphids contained 19 specimens of C. goepperti; two syninclusions contained ten specimens of Lasius schiefferdeckeri Mayr; and three syninclusions contained one specimen each: one Camponotus mengei Mayr, one Anonichomyrma constricta (Mayr), and one Formica flori Mayr. Considering that the Rovno and Saxonian collections are nearly equal in the number of amber pieces, the fundamental difference in the number of syninclusions is striking. The number of C. goepperti in syninclusions is disproportionately high; the proportion of syninclusions with aphids and C. goepperti is 1.6 times that of all inclusions of workers of this species. They are found in 31% of examined inclusions of workers in the collection of the Saxonian amber, but in 50% of syninclusions of the entire collection. This strongly suggests that C. goepperti and Germaraphis formed an association during their lifetime.  相似文献   

18.
New strophomenid and rhynchonellid (Brachiopoda) taxa are described from the Lower Pragian (Soda Creek Limestone) of west-central Alaska: Harperoides gen. nov. with type species H. alaskensis sp. nov. (subfamily Mesodouvillinae Harper et Boucot) and Pedderia gen. nov. with type species P. fragosa sp. nov. (family Pygmaellidae Baranov).  相似文献   

19.
Geckos of the genus Trigonodactylus are widely distributed in the sand deserts of the Arabian Peninsula. Three species of this genus are currently recognized, with a fourth one, Stenodactylus pulcher, which placement within Trigonodactylus has been tentatively suggested, but not yet confirmed. We present a phylogenetic analysis of the genus Trigonodactylus with new specimens collected in central Saudi Arabia and southern Jordan. New genetic data has been generated from three mitochondrial markers to investigate the phylogenetic relationships of all species of the genus and to assess the putative generic assignment of S. pulcher. Our results confirm that S. pulcher indeed belongs within Trigonodactylus, branching as a sister lineage to all other species of the genus. The new samples cluster within Trigonodactylus arabicus, thus confirming the genetic homogeneity of the species across its large and seemingly inhospitable range. The new specimen collected in southern Jordan represents the first record for the country and a considerable range extension to the northwest from all previously reported localities. Our findings and discovery of a new species for Jordan highlight the need of more field surveys to be carried out in the underexplored parts of Jordan and northern Saudi Arabia, as these places still hold a potential for new discoveries and are crucial for understating the biogeography of the Arabian herpetofauna.  相似文献   

20.
Yanliaoa is a common fossil in the Middle Jurassic of western Liaoning, eastern Inner Mongolia and northern Hebei Province, China. It is an important element of the Yanliao biota. The genus was established by Pan in 1977 for fossil plants from the Middle Jurassic Haifanggou Formation in Xiasanjiaochengzi, western Liaoning Province, and in present paper, the genus Yanliaoa is studied based on new material. Pan never designated a type specimen and his fossil material cannot be located. We designate a type specimen here for Yanliaoa, so that the genus name Yanliaoa remains valid. Yanliaoa sinensis Pan emend. Tan et al., is found in the same locality and formation as the lost specimens, Y. sinensis of Pan, 1977. Yanliaoa daohugouensis n. sp., a new species with epidermal anatomy, is from the Middle Jurassic Daohugou, Inner Mongolia. A holotype is also selected from the new material for this new species. Characters of the leafy shoots and ovulate cones of Yanliaoa are emended. The epidermal anatomy of this genus is described for the first time. Compared with other extant and extinct species of Cupressaceae s. l., the current species can be distinguished from any known species both by the leafy shoot characters and its epidermal anatomy. It further indicates that Yanliaoa is an extinct and endemic conifer found in the Middle Jurassic of northeastern China.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号