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《Comptes Rendus Palevol》2016,15(8):918-926
We describe a new species of mastodonsauroid temnospondyl from Algeria, Stanocephalosaurus amenasensis nov. sp., on the basis of two exquisite skulls from a Lagerstätte found in the lowermost formation of the Zarzaïtine Series, Illizi Basin, in the area of “La Reculée”, In Amenas region, Algeria. The new species is characterized by subtriangular nostrils with concave lateral borders; small orbits; postfrontals posteriorly very wide; very elongate parietals; smoothly concave posterior margin of the skull; ovoid anterior palatal vacuities; very posteriorly pointed choanae; oval interpterygoid fenestrae; and a short anterior extension of the cultriform process of the parasphenoid. S. amenasensis is different than the Algerian taxa previously erected by Lehman (1971)–“Parotosaurus lapparenti” and “Wellesaurus bussoni”–which we consider nomina dubia. It enlarges the distribution of the genus in northern Gondwana and supports the Early-Middle Triassic age of the lowermost formation of the Zarzaïtine Series. It also suggests that the local palaeoclimate was very seasonal and these aquatic amphibians died massively in a dewatering sebkha.  相似文献   
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Rhynchosauria was an important clade of herbivorous archosauromorph reptiles during the Triassic, with a worldwide distribution. We describe a new genus and species of early rhynchosaur, E ohyosaurus wolvaardti gen. et sp. nov. , from the early Middle Triassic (early Anisian) Cynognathus Assemblage Zone (Subzone B) of the Karoo Supergroup, South Africa. Eohyosaurus wolvaardti is known from a single skull, and is recovered as the sister taxon of Rhynchosauridae in a new phylogenetic analysis. Cynognathus Subzone B has previously yielded the stratigraphically oldest well‐understood rhynchosaur species, Mesosuchus browni and Howesia browni. Eohyosaurus wolvaardti increases the rhynchosaur diversity within this stratigraphical horizon to three species. Intriguingly, all currently confirmed rhynchosaur occurrences from the Early Triassic to earliest Middle Triassic are from South Africa. This may suggest a relatively restricted palaeogeographical distribution for early rhynchosaurs, followed by a global dispersal of rhynchosaurids during the Middle Triassic. © 2015 The Linnean Society of London  相似文献   
24.
Material of small sauropsids from the Otter Sandstone Formation of east Devon (Sherwood Sandstone Group; Middle Triassic; Anisian) includes remains that were formerly attributed to a primitive procolophonid. In the light of new specimens, this material is instead found to contain remains of a diapsid and a procolophonine procolophonid. Among these fossils, the medium-sized procolophonine, Kapes bentoni sp. nov., is the first record of this Russian genus in the British Triassic. Coartaredens isaaci gen. et sp. nov. is a small diapsid tentatively assigned to Lepidosauromorpha. The heterodont lower dentition of Coartaredens comprises a row of large, conical posterior teeth and tightly packed, procumbent incisiforms. Two additional specimens are distinguished on the basis of distinctive dentary remains. One of these is of possible procolophonid affinity, while the dentition of the second resembles that of the aberrant Early Triassic parareptilian genus Sclerosaurus .  相似文献   
25.
Thirty-five species belonging to 21 genera of foraminifers are distinguished from allochthonous limestone blocks contained within the autochthonous mudstones and sandstones of the Carnian Tanoura Formation, Kurosegawa Terrane of West Kyushu (SW Japan). These blocks are considered to be Anisian in age, based on the occurrence of two foraminifers widely distributed in the Anisian of the Tethyan Realm, Pilammina densa and Meandrospira dinarica; they are associated with Involutinid-like forms, such as Triadodiscus and Aulotortus, and with other foraminifers. The allochthonous limestones are mostly composed of oolites, abundant bioclasts and detrital quartz grains. They are thought to have been redeposited during the Carnian on the shelf slope of the South Kitakami-Kurosegawa Old Land. Palaeogeographically, this terrane was part of the North Gondwana margin, then isolated eastwards before its Early Cretaceous amalgamation with South China. Three foraminiferal species, Triadodiscus eomesozoicus (Oberhauser), Triadodiscus? tanourensis, n. sp., and Triadodiscus? sp. are described from the Anisian allochthonous blocks.  相似文献   
26.
Echinoid remains from the Triassic of China are described for the first time. The Middle Triassic of Qingyan in Guizhou Province, south-western China, has yielded nine taxa of primary spines; seven of these come from the lower Upper Anisian. Because all of the spines are disarticulated, the material is treated only parataxonomically. 'Cidaris' lineola (Bather) and 'Cidaris' wissmanni (Desor) are species originally described from the alpine Triassic of Europe. 'Cidaris' bangtoupoensis sp. nov., 'Cidaris' wachangpoensis sp. nov., 'Cidaris' venustespinosa sp. nov., 'Cidaris' fangchui sp. nov., 'Cidaris' gu sp. nov., 'Cidaris' mafengpoensis sp. nov. and 'Cidaris' sp. A are so far known only from Qingyan. Palaeoautecological interpretations based on the shapes of the spines fit well with the fact that the echinoids from Qingyan are part of highly diverse fossil associations which represent the remains of communities that lived in a protected, shallow-marine, stable soft-bottom habitat. The rather high diversity of the echinoid spines in terms of the number of both taxa and general types of shape shows that the echinoids, after nearly becoming extinct at the end of the Palaeozoic, began a new phase of adaptive radiation in the Anisian at the latest.  相似文献   
27.
盘县新民乡羊圈村及其邻区关岭组上段产出两种混鱼龙:Mixosaurus panxianensis Jiang et al. , 2006和Phalarodon of. P. fraasi Mcrriam. 1910.含混龟龙类化石层时代应为中二叠世安尼期Pclsonian亚期。“Mixosaurus yangjuanensis Liu and Yin, 2008”命名所依据的正模标本无关键的头骨特征。选取的头后骨骼做鉴定特征对混鱼龙类种一级分类无意义.鉴定特征所依据的基本骨块存在鉴定错误;“Mixosaurus maotaiensis”的厘定应无效;盘县动物群中无Mixosaurus cornalianus出现。  相似文献   
28.
The Pha Kan Formation that crops out at the Phra That Muang Kham section, south of Lampang city, was measured and sampled for ostracod analysis. We here report the occurrence of 29 species distributed among 14 genera. Four new species are described: Triassocypris phakanella Forel nov. sp., Leviella lampangensis Forel nov. sp., Bektasia yawella Forel nov. sp. and Hungarella poli Chitnarin nov. sp. The present data represent the first detailed report of Middle Triassic (Anisian) ostracods from the Sukhothai terrane and the first insight into diversity dynamics following the end-Permian extinction in this area. The ostracod assemblages of the Phra That Muang Kham section are discussed and document an important shift from siliciclastic to carbonate conditions, from a protected to an open marine environment, followed by a slight regressive trend up-section associated with repeated salinity fluctuations. This fauna illustrates the post-crisis recovery during the Middle Triassic and some hypothesis are issued on the distribution pathways of several taxa.  相似文献   
29.
广西中三叠世的"克氏蛤"之订正   总被引:1,自引:1,他引:0  
描述报道广西中三叠世地层中一类形态相似于克氏蛤(Claraia)的双壳纲化石,经研究,发现海扇科的关键特征丝梳,认为不属于克氏蛤,而可能是Periclaraia属的一个新种,并初步探讨化石层的生态环境,认为可能是相对隔离的盆地中央区,新种是由海扇类进入隔离环境后经特化形成的,新种与克氏蛤的表面相似性是生活习性的相似性导致的形态趋同现象。  相似文献   
30.
The Triassic algal species Solenopora concentrica Senowbari-Daryan, Link & Isintek (2006) is renamed to S. isoconcentrica.  相似文献   
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