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A partial postcranial skeleton (carapace, plastron, and other poorly preserved elements) of a turtle, from the late Oxfordian of the Betic Range of Spain, has recently been assigned to a new taxon, Hispaniachelys prebetica. This is one of the few European turtle taxa reported from pre-Kimmeridgian levels, and the oldest turtle so far known from southern Europe. The character combination identified in that taxon (including the presence of cleithra, and single cervical scale) did not allow its assignment to Plesiochelyidae, a group of turtles very abundant and diverse in the Late Jurassic of Europe. The revision of the single specimen assigned to this taxon led to the reinterpretation of some of its elements, being reassigned to Plesiochelyidae. This study confirms the presence of Plesiochelyidae in the Oxfordian. However, because the Spanish taxon does not present a unique combination of characters, it is proposed as a nomen dubium.
Chitracephalus dumonii was named based on some of the most complete turtle remains from the Lower Cretaceous of Europe, and yet the taxon has barely been mentioned since. Indeed, new specimens were erroneously attributed to a new taxon, “Salasemys pulcherrima”. The synonymy is recognized here, and this extends the geographical range of this turtle and provides examples of individuals at different stages of ontogenetic development. The peculiar structure of its shell, and its ontogenetic development, are unique to this taxon. The systematic position of C. dumonii was previously unclear, usually being referred to Testudinata incertae sedis. Here, it is placed in a cladistic analysis, which shows that C. dumonii, and the recently described Hoyasemys jimenezi form part of a Lower Cretaceous European clade of Cryptodira that includes “macrobaenid”, “sinemydid”, and panchelonioidean turtles.
Brodiechelys brodiei is an Early Cretaceous turtle from Great Britain, the only species of the genus. This taxon has been shown in recent phylogenies to be closely related to Xinjiangchelyidae and therefore could be the only representative of this group in Europe. Here, we present several specimens from the Early Cretaceous Maestrazgo Basin, in the Iberian Range of Spain attributed to the British genus, and to a new species, Brodiechelys royoi. This discovery shows that, as previously observed with terrestrial turtles, some freshwater turtle taxa had a wide European distribution during the Early Cretaceous, being present in both Britain and the Iberian Peninsula. This study sheds new light on the phylogenetic position of this enigmatic genus, supporting its attribution to Xinjiangchelyidae, a clade whose presence has been previously confirmed exclusively from the Middle Jurassic to Early Cretaceous of Asia. We propose that another recently identified taxon from the Iberian Peninsula (i.e., Larachelus morla) is also a member of this clade. Recent studies have identified several continental taxa of the clade that included the members of “Macrobaenidae” and “Sinemydidae” in Europe. This study provides new evidence of close relationships between the Early Cretaceous turtle faunas from Europe and Asia.
Simosaurus is a Triassic eosauropterygian genus known from cranial and postcranial elements, found in the Middle and Upper Triassic strata of Europe and the Middle East. Simosaurus gaillardoti is currently recognised as the only valid species of the genus, identified in Ladinian strata of an area that includes northeastern France (Lorraine) and southwestern Germany (Baden-Württemberg). The remains from this area include more than 20 skulls. Although some of them were described in detail and figured by several authors since the discovery of S. gaillardoti, many others remained unpublished. Here we study and figure 25 skulls from this taxon, reviewing the previously known specimens, and presenting and analyzing numerous unpublished skulls. This significant sample of skulls from a single taxon of a European Triassic eosauropterygian allows us to recognise intraspecific variability in characters previously identified as non-variable in this species, including some that are often included in phylogenetic analyses of these reptiles. Therefore, we markedly increase our knowledge of the cranial skeleton in this taxon.
A freshwater turtle from the lithographic limestone of Las Hoyas (Barremian of Cuenca, Spain) is described as a new genus and species of Eucryptodira, Hoyasemys jimenezi. The holotype consists of the skull, lower jaw, carapace, plastron, vertebral column, pectoral and pelvic girdle remains, and foreand hindlimbs. Hoyasemys jimenezi gen. et sp. nov. is characterized by three pairs of blind oblique depressions on the ventral surface of the basisphenoid, and a character combination composed, among others, of the articulation between the fourth and fifth cervical vertebrae through a cotyle in the fourth and a condyle in the fifth, amphicoelous caudal centra, and most digits of manus and pes with three elongated phalanges. This study allows clarification of the systematic position of a species of uncertain affinity often identified as “chelydroid” in appearance. A phylogenetic analysis shows Hoyasemys jimenezi gen. et sp. nov. forms a monophyletic group with Judithemys sukhanovi, Dracochelys bicuspis, Sinemys lens, and Ordosemys leios, collectively the sister group of crown Cryptodira.
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