58 research outputs found

    New finds of anguines (Squamata, Anguidae) from the Early Miocene of Northwest Bohemia (Czech Republic)

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    New material on anguines is described from two Lower Miocene localities in Northwest Bohemia in the Czech Republic: Merkur (MN 3) and Dolnice (MN 4). Although the material is disarticulated, it was possible to assign several elements to one species based on similar ornamentation of the skull roof bones and similar morphology of the teeth. Two new species, Ophisaurus holeci nov. sp. and Pseudopus rugosus nov. sp. are described. Pseudopus rugosus becomes the second species of the genus Pseudopus described from the Merkur locality. In addition to the new Ophisaurus species above, the species O. spinari is described on the basis of the parietal and Ophisaurus sp. 1 and Ophisaurus sp. 2 on the basis of the frontal bones. A further five anguines, designated Anguine morphotypes 1 to 6, are described on the basis of the marginal teeth bearing elements (premaxilla, maxilla and dentary) and on the pterygoid, the angular bone and elements forming the posterior portion of the lower jaw. The described specimens present a relevant contribution to our knowledge of the diversity of anguines in the Early Neogene of Europe

    First record of fossil anguines (Squamata; Anguidae) from the Oligocene and Miocene of Turkey

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    Fossil anguine lizard specimens from several Turkish localities are described in this paper. The material comes from ten different localities, spanning a large geographic area consisting of both parts of the European Turkey and Anatolia, and ranging in age from the Oligocene to the Late Miocene. In certain cases, the generic determination was possible and, accordingly, members of Ophisaurus and Anguis were identified and described in detail. The specimens of Anguis, found in different, Middle and Late Miocene localities from Anatolia, represent two of only a few fossil occurrences of this taxon. Moreover, the material reported herein represents the oldest occurrences of anguine lizards, not only from Turkey, but from southeastern Europe and the Eastern Mediterranean basin as a whole. These rare records provide important information about the dispersal routes of anguines from Europe to Asia and significantly enhance our understanding of their biogeography

    Braincase and Inner Ear Anatomy of the Late Carboniferous Tetrapod Limnoscelis dynatis (Diadectomorpha) Revealed by High-Resolution X-ray Microcomputed Tomography

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    The braincase anatomy of the Pennsylvanian diadectomorph Limnoscelis dynatis is described in detail, based upon high-resolution X-ray microcomputed tomography. Both supraoccipitals and most of the prootics and opisthotics are preserved. The known portions of the left prootic, opisthotic, and supraoccipital enclose complete sections of the endosseous labyrinth, including the anterior, posterior, and lateral semicircular canals, the vestibule, the cochlear recess, and the canal for the endolymphatic duct. The fossa subarcuata is visible anteromedial to the anterior semicircular canal. The presumed endolymphatic fossae occur in the dorsal wall of the posteromedial portion of the supraoccipital. Both the fossa subarcuata and the fossa endolymphatica lie in the cerebellar portion of the cranial cavity. In order to investigate the phylogenetic position of L. dynatis we used a recently published data matrix, including characters of the braincase, and subjected it to maximum parsimony analyses under a variety of character weighting schemes and to a Bayesian analysis. Limnoscelis dynatis emerges as sister taxon to L. paludis, and both species form the sister group to remaining diadectomorphs. Synapsids and diadectomorphs are resolved as sister clades in ∼90% of all the most parsimonious trees from the unweighted analysis, in the single trees from both the reweighted and the implied weights analyses, as well in the Bayesian tree

    A review of Coelostegus prothales Carroll and Baird, 1972 from the Upper Carboniferous of the Czech Republic and the interrelationships of basal eureptiles

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    We redescribe the holotype and only known specimen of the early eureptile Coelostegus prothales from the Upper Carboniferous of the Czech Republic using photogrammetric CT scanning and a virtual 3D rendition of its skull bones. New information is available on several skull and lower jaw bones, including the postorbital, supratemporal, tabular, postparietal, angular, and prearticular. The new data also permit the correct identification of previously undetected or misidentified elements (e.g., supratemporal; quadratojugal; angular). We provide an amended diagnosis of Coelostegus and a new reconstruction of the skull in dorsal and lateral views. To- evaluate the affinities of Coelostegus, we code this taxon in two recently published taxon-character matrices. Parsimony and Bayesian analyses do not permit firm conclusions on the phylogenetic position of Coelostegus or, indeed, the status and extrinsic relationships of protorothyridid amniotes. Coelostegus emerges either as the sister taxon to the recently redefined Diapsida (Araeoscelidia; Varanopidae; Parareptilia; Neodiapsida), as one of the most basal protorothyridids, or as a derived stem-group amniote in various parsimony-based analyses, or as the basalmost protorothyridid in one Bayesian analysis, with protorothyridids forming a paraphyletic array relative to Diapsida. We review the cranial similarities and differences between Coelostegus and other protorothyridid genera and discuss the implications that various phylogenetic results have for our understanding of early amniote relationships

    A new species of Varanus (Anguimorpha: Varanidae) from the early Miocene of the Czech Republic, and its relationships and palaeoecology

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    Skeletal remains of a new early Miocene (Ottnangian, MN 4 mammal zone) monitor lizard, Varanus mokrensis sp. nov., are described from two karst fissures in the Mokrá-Western Quarry (1/2001 Turtle Joint; 2/2003 Reptile Joint), Czech Republic, providing the first documented example of a European varanid for which osteological data permit a well-supported assignment to the genus Varanus. The new species is morphologically similar to the Recent Indo-Asiatic varanids of the Varanus bengalensis group. It differs from all other Varanus species on the basis of a single autapomorphy and a combination of 11 characters. As a distinguishing feature of V. mokrensis, the parietal and squamosal processes of the postorbitofrontal form a narrowly acute angle. The teeth show distinct, smooth cutting edges along the mesial and distal margins of the apical portion of their crowns. This feature is not observed in most extant Asiatic Varanus species and may represent a plesiomorphic condition. The results of parsimony phylogenetic analyses, with and without character reweighting, reveal poor resolution within Varanus. A Bayesian analysis shows V. mokrensis to be closely related to extant representatives of the Indo-Asiatic Varanus clade, with close affinities to the V. bengalensis species group. The topology of the Bayesian tree supports the hypothesis that Miocene monitors from Mokrá are representatives of a lineage that is ancestral to the well-defined clade of extant African varanids, including the early Miocene V. rusingensis. In addition, our results support a Eurasian origin for the varanid clade. The extant African Varanus species probably originated in the late Oligocene. The radiation of African varanids probably occurred during the late Oligocene to early Miocene time interval. The occurrence of Varanus in the early Miocene of Mokrá-Western Quarry corresponds to the warm phase of the Miocene Climatic Optimum. Remains of a diverse aquatic and heliophobe amphibian fauna at the 2/2003 Reptile Joint site indicate more humid conditions than those at the 1/2001 Turtle Joint site

    Figure 4 in The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia

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    Figure 4. Karpinskiosaurus secundus (Amalitzky, 1921), PIN 4617/158. Photographs of partly disarticulated skull in dorsal (A) and lateral (B) views.Published as part of <i>Klembara, Jozef, 2011, The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia, pp. 184-212 in Zoological Journal of the Linnean Society 161 (1)</i> on page 190, DOI: 10.1111/j.1096-3642.2009.00629.x, <a href="http://zenodo.org/record/10114728">http://zenodo.org/record/10114728</a&gt

    Figure 1 in The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia

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    Figure 1. Karpinskiosaurus secundus (Amalitzky, 1921), PIN 2005/81 (holotype). Photographs of skull in dorsal (A), ventral (B), dorsolateral (C), and ventral (D) views.Published as part of <i>Klembara, Jozef, 2011, The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia, pp. 184-212 in Zoological Journal of the Linnean Society 161 (1)</i> on page 186, DOI: 10.1111/j.1096-3642.2009.00629.x, <a href="http://zenodo.org/record/10114728">http://zenodo.org/record/10114728</a&gt

    Figure 5 in The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia

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    Figure 5. Karpinskiosaurus secundus (Amalitzky, 1921), PIN 4617/158. A, photograph of anterolateral portion of skull in lateral view. B, outlines of several bones of the same specimen.Published as part of <i>Klembara, Jozef, 2011, The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia, pp. 184-212 in Zoological Journal of the Linnean Society 161 (1)</i> on page 191, DOI: 10.1111/j.1096-3642.2009.00629.x, <a href="http://zenodo.org/record/10114728">http://zenodo.org/record/10114728</a&gt

    Ontogeny of the partial secondary wall of the otoccipital region of the endocranium in prehatchingAlligator mississippiensis (Archosauria, Crocodylia)

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    The ontogeny of the posterior otic and anterior occipital portions of the neural endocranium of prehatching Alligator mississippiensis was investigated by reconstruction from sectioned material. In Stage 6 of this species, in which the endochondral ossification of the otoccipital region of the neural endocranium is only in its very early stage, two bony outgrowths—laminae—are present at the external wall of the posterior portion of the neural endocranium. The anterior lamina arises from the external surface of the basal plate at the level of the posterior margin of the subcapsular process; the posterior lamina arises from the external surface of that portion of the pila occipitalis that forms the posteroventral wall of the metotic fissure. During ontogeny, both laminae lying in the anteroposterior sequence ossify in membrane, fuse together, grow laterodorsally, and fuse with the lateral wall of the lateral semicircular canal and the crista parotica. This lamina forms a new, secondary wall enclosing the posterior section of the otic capsule and contains the large external jugular foramen (or foramen vagi) in its basal portion. The laminae, designated lamina juxtaotica anterior and posterior (lamina juxtaotica when fused together), have not been recorded previously in crocodylians and are absent in all other Recent reptiles. From the functional point of view, the juxtaotic lamina 1) forms the margins of the external jugular foramen, and 2) forms the floor of the posterior section of the Eustachian tube. In birds, the structure called the metotic cartilage, which arises in ontogeny as an independent element, has a similar position as the juxtaotic lamina. However, the two structures differ in their developmental origins and their relation to the Eustachian tube and the ramus hyomandibularis of the facialis nerve. Moreover, there is no external jugular foramen in birds

    Figure 6 in The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia

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    Figure 6. Karpinskiosaurus secundus (Amalitzky, 1921), PIN 4617/158. A, photograph of palatine through right orbit in dorsal view. B, outline of palatine of the same specimen in dorsal view.Published as part of <i>Klembara, Jozef, 2011, The cranial anatomy, ontogeny, and relationships of Karpinskiosaurus secundus (Amalitzky) (Seymouriamorpha, Karpinskiosauridae) from the Upper Permian of European Russia, pp. 184-212 in Zoological Journal of the Linnean Society 161 (1)</i> on page 191, DOI: 10.1111/j.1096-3642.2009.00629.x, <a href="http://zenodo.org/record/10114728">http://zenodo.org/record/10114728</a&gt
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