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A new metriorhynchid crocodylomorph from the Lower Kimmeridge Clay Formation (Kimmeridgian, Upper Jurassic) of England is described. This specimen, a three‐dimensionally preserved skull and left mandibular ramus, is referred to a new species: T orvoneustes coryphaeus sp. nov. Within the genus Torvoneustes, T . coryphaeus sp. nov. is unique as it has a long anteromedial process of the frontal, ornamented dermatocranium, and the supraorbital notch forms a strongly acute angle. Our phylogenetic analysis confirms the placement of this specimen in Torvoneustes. The dentition of T . coryphaeus sp. nov. , like that of the type species, has a blunt apex, crown basal–mid regions with numerous tightly packed apicobasally aligned ridges, and apical region with an anastomosed pattern of ridges that interact with the carinae. Within Thalattosuchia these dental characteristics are only found in Torvoneustes and the teleosaurid Machimosaurus. The heavily ornamented dermatocranium of T . coryphaeus sp. nov. is in contrast to the unornamented (nasals and frontal)–lightly ornamented (maxillae and premaxillae) pattern seen in Torvoneustes carpenteri. Curiously, this pattern of reduction and loss of dermatocranium ornamentation is also observed in Metriorhynchus, Dakosaurus, and the subclade Rhacheosaurini. We hypothesize that the ‘smooth’ dermatocranium of Late Jurassic metriorhynchids evolved independently in each subclade (parallel evolution), and would have reduced drag, thereby making locomotion through water more energy efficient. © 2013 The Linnean Society of London  相似文献   

3.
Abstract

A new Megalopidae (Teleostei, Elopomorpha, Elopiformes), Protarpon boualii sp. nov., is described on the basis of two neurocrania gathered from the Lower Palaeocene (Danian) beds of the Oulad Abdoun basin, in Morocco. Its inclusion in the family Megalopidae and the genus Protarpon is supported by the L-shaped pterotics, the flat skull roof, the well developed epiotic processes and the roofed dilatator fossae. It differs from Protarpon priscus and P. oblongus from the Ypresian of the London Clay Formation (England) mainly by the proportions of the subtemporal and the post-temporal fossa openings, the proportions of skull roof bones and its larger size. Protarpon boualii sp. nov. represents the first fossil occurrence of a megalopid in North Africa. Its close phylogenetic relationships with forms from the London Clay Formation highlight the strong biogeographical affinities between the faunas of these two localities during the Palaeocene-Eocene period.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:D5FEE8B3-B220-461F-B635-31DD7F2CF921  相似文献   

4.
We report the only definite specimen of the teleosaurid crocodylomorph genus Machimosaurus from the Kimmeridge Clay Formation of England. This specimen (an isolated tooth) is now the only evidence of Machimosaurus in the Kimmeridge Clay Formation because a large skull and mandible, previously considered to be of Machimosaurus mosae, was recently shown to pertain to a metriorhynchid crocodylomorph. The tooth described herein was originally figured in 1884 as a tooth crown from a metriorhynchid crocodylomorph. However, its conical shape, blunt apex and distinctive enamel ornamentation are characteristic of the teleosaurid genus Machimosaurus. That Machimosaurus, and teleosaurids in general, were so rare in the Kimmeridge Clay Formation suggests that these marine crocodylomorphs did not commonly use this seaway. Their rarity is in contrast to contemporaneous deposits from continental Europe where teleosaurid remains, including Machimosaurus, are far more common. These continental deposits were deposited in shallow-marine/brackish ecosystems, suggesting that teleosaurids were largely restricted to coastal marine environments.  相似文献   

5.
We report the largest known British specimen of the metriorhynchid crocodylomorph genus Dakosaurus discovered offshore from Chesil Beach, Dorset, England (Kimmeridge Clay Formation). This specimen is large toothed, which has extreme enamel spalling on the labial surface, enlarged carinae (‘carinal flanges’), carinal wear, macroziphodont denticles, and the crown retains much of its labiolingual width along most of its apicobasal length. This suite of morphologies is unique to Dakosaurus. All known Kimmeridge Clay Formation Dakosaurus specimens are isolated tooth crowns. A skull previously referred to Dakosaurus lacks all the cranial apomorphies of D. maximus and D. andiniensis, and cannot be referred to this genus. Furthermore, the vast majority of putative Dakosaurus tooth crowns from the ‘Potton Sands’ ( = Woburn Sands Formation) do indeed represent Dakosaurus (as well as two Plesiosuchus specimens), and they most likely originate from the Kimmeridge Clay Formation.  相似文献   

6.
Abstract

We report a new dimylid species, Plesiodimylus ilercavonicus sp. nov., from the Early Miocene locality of Mas d’Antolino B-5 (Ribesalbes-Alcora, Castelló, Spain). This new species of Plesiodimylus is an amblyodont form of the genus and exhibits some primitive characters. The phylogenetic and palaeoenvironmental implications of this southern occurrence of Plesiodimylus in Lower Miocene sediments are discussed.

http://zoobank.org/lsid:zoobank.org:pub:E78DB979-6552-4BE2-BEC9-FA2EA05B7B39  相似文献   

7.
An anatomical and taxonomic analysis of the mammalian record in the locality of La Poma in Salta Province, Argentina, is here presented. This record consists in two specimens exhumed in levels of the Quebrada de los Colorados Formation referred to the middle late Eocene. The first specimen is represented by a partial skull preserving mostly the rostrum and some dental pieces and was identified as a member of Leontiniidae, although it does not bear enough information for generic or specific determination. The second specimen is represented by more complete material, preserving much of the dentition. It was identified as a new species of the genus Pampahippus, traditionally included in the paraphyletic family Notohippidae. The leontiniid here studied presents several plesiomorphic features identified in other taxa of northwestern Argentina, and this material represents a new example of a pre-Deseadan basal morphotype within the family. Regarding the new species of Pampahippus, it shows clear signs of rising hypsodonty, representing the first case for a notoungulate lineage in the Paleogene of northwestern Argentina.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:45D87764-5B63-4487-BAAC-74F8D490AE18  相似文献   


8.
Bivalves have been found in unique benthic assemblages associated with active methane seeps and mounds along the western and southern margins of the Svalbard shelf (75–79°N) at 350–380?m depth. Among the samples collected were a number of shells of Thyasiridae that are distinct from any species previously described. Here we describe one new genus Rhacothyas gen. nov. and two new species Thyasira capitanea sp. nov. and Rhacothyas kolgae sp. nov., including their distinguishing characteristics and the environmental setting where they were found. Thyasira capitanea sp. nov. is large compared with many other thyasirids, has an equilateral shell and demarcated zones on the median and anterior areas along with a distinct posterior sulcus. Rhacothyas kolgae sp. nov. is unique among other thyasirid genera and species regarding its characteristic outline, sunken lunule, lack of submarginal sulcus and wrinkled surface. Furthermore, we discuss their present occurrence in the context of the glaciomarine history of the Svalbard margin. We posit that these new species, after the deglaciation of the Barents Sea Ice Sheet, may have originated from other chemosynthetic or reducing environments along the Atlantic shelf margin or the southern Barents Sea shelf by following the net transport of the North Atlantic Current rather than having evolved in situ.

http://zoobank.org/urn:lsid:zoobank.org:pub:0F3DCFD6-05C9-4E76-803E-655ACD3AF335  相似文献   


9.
A new pectinodontid species collected from sunken wood in the East China Sea off Zhejiang Province, China, is described and assigned to the genus Pectinodonta Dall, 1882. This new species, Pectinodonta mazuae n. sp., has a medium sized shell with a fine sculpture; shell width about 72%–75% of shell length, height about 61%–66% of length, and each lateral tooth has 16 or 17 cusps. These features may be used to distinguish the new species from its congeners.

http://zoobank.org/urn:lsid:zoobank.org:act:4B3D491F-868D-4F9A-8CC9-005829BF691E  相似文献   


10.
Hedychrum zenobia sp. n. is described from Syria and Iraq, and H. linsenmaieri sp. n. from Pakistan. They belong to the H. cirtanum species group hereby established, which includes some of the largest Palaearctic Hedychrum species, characterised by a modified metascutellum projecting over the propodeum, a deep mid-tibial groove in the male and an apicomedial tooth on the third metasomal sternum in the female. Hedychrum cirtanum var. minusculum du Buysson, 1898 is transferred to the genus Hedychridium Abeille de Perrin, 1878 and elevated to species rank as Hedychridium minusculum (du Buysson, 1898) stat. n.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:DE7B4BF7-3E4B-4664-8F3A-1FD480F72A41  相似文献   


11.
12.
We describe the otolith assemblage from the early Miocene (Burdigalian) exposures of the Castillo Formation at the Cerro La Cruz locality (Falcón Basin, Lara State, northwestern Venezuela). The samples were obtained through surface and bulk sampling at distinct stratigraphic levels of the study area. The otolith assemblage from Cerro La Cruz includes 14 families, 25 genera and 30 taxa, of which 20 are reported for first time from the Castillo Formation. These include two new sciaenid taxa, Ctenosciaena angusticaudata nov. sp. and Pareques laraensis nov. sp. The Castillo Formation otolith assemblage represent fishes typical of shallow and near-shore and coral reef associated environments as characterized primarily by a high taxonomic diversity and abundance of Sciaenidae, and the lack of mesopelagic families (Myctophidae). The faunal composition of Cerro La Cruz is similar to other chronological equivalent sedimentary units along the proto-Caribbean area (Pirabas and Cantaure formations; Brazil and Venezuela respectively), though the Castillo Formation fish fauna shows lower taxonomic diversity, suggesting some heterogeneity of the coastal and near shore marine environments along the southern portion of the proto-Caribbean.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B79F51B8-BC35-4119-8957-84544286868D  相似文献   


13.
Extant baleen whales (Cetacea, Mysticeti) are a disparate and species‐rich group, but little is known about their fossil record in the northernmost Atlantic Ocean, a region that supports considerable extant cetacean diversity. Iceland's geographical setting, dividing North Atlantic and Arctic waters, renders it ideally situated to shed light on cetacean evolution in this region. However, as a volcanic island, Iceland exhibits very little marine sedimentary exposure, and fossil whales from Iceland older than the late Pleistocene are virtually unknown. Here, we present the first fossil whale found in situ from the Pliocene Tjörnes Formation (c. 4.5 Ma), Iceland's only substantial marine sedimentary outcrop. The specimen is diagnosed as a partial skull from a large right whale (Mysticeti, Balaenidae). This discovery highlights the Tjörnes Formation as a potentially productive fossil vertebrate locality. Additionally, this find indicates that right whales (Eubalaena) and bowhead whales (Balaena) were sympatric, with broadly overlapping latitudinal ranges in the Pliocene, in contrast to the modern latitudinal separation of their living counterparts.  相似文献   

14.
Two new species Apsilochorema (Apsilochorema) shalimarensis sp. n. and Apsilochorema (Apsilochorema) sainii sp. n. are described and illustrated from India. With these new additions, the genus Apsilochorema Ulmer, 1907 is now represented by 14 species from India.http://www.zoobank.org/urn:lsid:zoobank.org:pub:AAA8C469-850E-4778-BCF1-3FF5B429E559  相似文献   

15.
New material of freshwater molluscs in the Mediterranean region of Turkey revealed two new species of the genus Pseudamnicola Paulucci, 1878, i.e., P. kayseriensis n. sp., and P. gullei n. sp.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:3E39E467-22A5-4091-9975-17343DA8D02E  相似文献   

16.
A new species of pseudoscorpion of the genus Calocheiridius Beier &; Turk, Calocheiridius iranicus n. sp., is described from Markazi province, Iran. Illustrations and measurements of the species are given. http://www.zoobank.org/urn:lsid:zoobank.org:pub:06332B5C-D43A-4955-AB6C- 5847D10C2BAC  相似文献   

17.
Summary

Three new trechine species of the genus Pilosaphaenops Deuve & Tian, 2008, P. qianzhii n. sp. from cave Lubian Dong in Pingtang County, southern Guizhou Province, P. mengzhenae n. sp. and P. weiguofui n. sp. from cave Xia Dong in Nandan County, and cave Shenlong Gong in Huanjiang County respectively, northern Guangxi Zhuang Autonomous Region, are described and illustrated. A key to all known species of this genus is also provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:170C467F-5421-49AD-B1B1-091D8BD58B88  相似文献   

18.
We report on a new species of basal ornithuromorph bird, Piscivoravis liigen. et sp. nov., based on a well-preserved and nearly complete specimen from the Lower Cretaceous Jiufotang Formation in western Liaoning Province, northeastern China. The new specimen preserves several unique anatomical features previously unreported in Early Cretaceous ornithuromorphs, such as a robust furcula with strongly tapered omal tips, a broad sternum without craniocaudal elongation and large and strongly curved manual unguals. Phylogenetic analysis indicates that Piscivoravis is more derived than Archaeorynchus, but in a basal polytomy with Jianchangornis, Patagopteryx, and the clade including all more derived ornithuromorphs. The preserved wing and tail feathers provide new information on feather diversity and evolution in Early Cretaceous ornithuromorphs. The preservation of fish bones ventral to the dentary and in the stomach provides direct evidence that the new species was piscivorous – previously only reported in Yanornis, and as in some living birds, was capable of moving food bidirectionally through the alimentary canal.http://www.zoobank.org/urn:lsid:zoobank.org:pub:92F23126-9E89-4E51-9700-C6608E0D66EB  相似文献   

19.
A remarkable new genus of tribe Opsiini (Deltocephalinae), Yinformibus gen. nov. including Yinformibus menglaensis sp. nov. is described from Yunnan of China. The new genus is placed in the tribe Opsiini based on male adults having a pair of aedeagal shafts, each with its own gonopore. Partial 28S rDNA and Histone H3 sequences are provided for the new species, and a phylogenetic analysis based on these markers for Deltocephalinae retrieved from GenBank suggests Opsiini is monophyletic and supports the placement of Yinformibus gen. nov. in Opsiini. The molecular results placed the new genus in a clade comprising Hishimonus Ishihara, Opsius Fieber, and an undescribed genus from Zambia. Additionally, we also analysed the relationships of Yinformibus gen. nov. with other genera based on morphology.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:85C23AC3-8B19-4F29-9F55-BFC392242B51  相似文献   


20.
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