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Prolacerta broomi is one of the most important of fossil reptiles. First considered as one of the earliest members of squamates, this basal archosauromorph has been used as a model for diapsid morphological evolution ever since its discovery, playing a pivotal role in hypotheses on the origin of diapsid reptiles. The holotype of Prolacerta broomi (UCMZ 2003.41R) is known from a mostly complete skull, but the original description is limited to the superficial features of the skull roof and palate. Since then, many other specimens of Prolacerta broomi have been recovered that potentially account for this limited access to anatomical information, but it remains unclear whether these aspects correspond well to the known material of the holotype. Here, the skull morphology of the holotype of Prolacerta broomi is revisited through the use of μCT scans. The identifications of some cranial elements have been corrected, such as the left prefrontal and lacrimal, and several new elements are revealed, including the epi- and ectopterygoids, prearticular, coronoid, and braincase bones. The orbitonasal region is described in detail and significantly shows a contribution of the lacrimal to the dorsal alveolar canal. Finally, the addition of the holotype as an independent OTU in recently published analyses indicate conflicts with the current knowledge on Prolacerta broomi phylogenetic affinity and taxonomy. First, it points to potential taxonomic inconsistency since the holotype does not form a monophyletic group with other Prolacerta broomi OTUs in any of the analyses and, second, it suggests a more basal position for the holotype than that recovered in some studies, more basal than rhynchosaurs and close to the origin of Crocopoda. Together, these findings indicate areas of future research interest in the study of early evolving archosauromorphs. [ABSTRACT FROM AUTHOR]

We introduce the new vertebrate site of La Piquera (Duero Basin, central Iberian Peninsula), provide a detailed description of the lithostratigraphy and present a preliminary faunal list. The fossil vertebrate association includes amphibians (with representatives of the families Salamandridae, Alytidae, Pelodytidae, and Bufonidae), squamate reptiles (with members of the families Agamidae, Lacertidae, Anguidae, Scincidae, Blanidae, 'Erycidae, and Colubridae/Psammophiidae), and mammals (with representatives of the families Soricidae, Erinaceidae, Muridae, Cricetidae, Gerbillidae, Gliridae, Sciuridae, Vespertilionidae, Rhinolophidae, Miniopteridae, Megadermatidae, Leporidae, Prolagidae, and Bovidae). The association indicates an intermediate biostratigraphic position between the southern Iberian sites of Sifón-413 (at about 5.33-5.23 Ma) and Botardo-D (between 4.79 and 4.63 Ma), the new locality being correlated with the earliest Ruscinian (lower part of the MN14 unit). The ecological affinities of the identified small vertebrates suggest the presence of a landscape dominated by open herbaceous meadows in the surroundings of the fossil-site during the earliest Pliocene, with the occasional presence of woodland patches and stable water bodies under relatively dry and warm environmental conditions. La Piquera therefore enhances our knowledge on the vertebrate community recorded in central Iberian Peninsula during the earliest Pliocene. With more than 1200 remains, La Piquera becomes a key locality for the Early Pliocene of southwestern Europe, central Spain, where this time-span is poorly represented. [ABSTRACT FROM AUTHOR]

Rhynchosaurs were key herbivores over much of the world in the Middle and Late Triassic, often dominating their faunas ecologically. The anatomy of the Middle Triassic forms is debated in certain phylogenetically important details. Among several genera from the Anisian of England, Bentonyx sidensis is represented by a near-complete skull. New CT scanning of the holotype skull reveals previously concealed details of the palate and braincase in particular, and this allows comparison with other Middle Triassic rhynchosaurs and confirmation that Bentonyx is a distinct taxon from others of similar age including Fodonyx, Rhynchosaurus, Langeronyx, and Stenaulorhynchus. These are part of the first wave of rhynchosaur diversification in the Middle Triassic. [ABSTRACT FROM AUTHOR]

The herpetofaunal biodiversity of West Indies suffered a significant change during the last few million years that is well documented for some squamate reptilies (lizards). However, almost nothing is known about past biodiversity of snakes, which are active predators and important component of terrestrial ecosystems. Here we describe the fossil remains of snakes (Reptilia: Serpentes) from the late Pleistocene of El Abrón Cave, Cuba. This is the first representative assemblage of fossil snakes from Cuba. It allows us to evaluate the taxonomic diversity of snakes in the Pleistocene of the island for the first time. The material includes eight taxa from the four snake families: cf. Cubatyphlops (Typhlopidae), Tropidophis melanurus, Tropidophis sp., Cubophis cf. cantherigerus, Arrhyton sp., cf. Caraiba andreae, Dipsadidae indet., and Natricidae indet. (Natricidae). Two (Dipsadidae indet. and Natricidae indet.) are not known in the modern fauna of Cuba. The assemblage from El Abrón Cave shows that ophidian Pleistocene assemblage was different from modern snake fauna of Cuba and was probably more diverse at genus level than it is now. Most of taxa revealed in El Abrón Cave were not previously known in the fossil record. [ABSTRACT FROM AUTHOR]

Sauropterygia, one of the main clades of Mesozoic marine reptiles, diversified shortly after the Permo-Triassic biotic crisis and afterwards remained one of the major components of Early Triassic and later Mesozoic marine ecosystems. On the other hand, actual specimens of marine reptiles of Olenekian age are still rare in the fossil record, coming only from a few localities worldwide. Here we describe associated remains of a larger marine reptile of around 4 m body length, with nothosauroidean affinities from the Sulphur Mountain Formation exposed at the L cirque locality of Wapiti Lake area in British Columbia. Although the specimen records only scattered parts of the posterior vertebral column, some gastral ribs and most notably, the proximal portion of one hind limb together with a fan-shaped ischium, it represents one of the oldest records of Sauropterygia and larger representatives of aff. Nothosauroidea specifically, as well as the northernmost occurrence of such animals in the Triassic. As such, the new specimen is important for understanding the biogeography and early evolution of the group and that of Sauropterygia, in general. [ABSTRACT FROM AUTHOR]

Fossil turtles are one of the least studied clades in regard to endocranial anatomy. Recently, the use of non-invasive technologies, such as radiographic computed tomography (CT), increased the knowledge of the neuroanatomy of several extinct and extant taxa. Here, we provide the description of the nasal cavity, cranial endocast, and inner ear of the stem turtle Naomichelys speciosa based on digital 3D reconstructions. This terrestrial form is characterized by a nasal cavity with anteroposteriorly elongated vestibulum and a large cavum nasi proprium, traits typically related to terrestrial habits. The large olfactory region of the cavum nasi proprium suggests that olfaction was probably the most important sense for this species. Our description of N. speciosa adds novel information to the knowledge of endocranial anatomy in early turtle evolution and provides an important foundation for future analyses and comparisons. [ABSTRACT FROM AUTHOR]

Sauropterygia, one of the main clades of Mesozoic marine reptiles, diversified shortly after the Permo-Triassic biotic crisis and afterwards remained one of the major components of Early Triassic and later Mesozoic marine ecosystems. On the other hand, actual specimens of marine reptiles of Olenekian age are still rare in the fossil record, coming only from a few localities worldwide. Here we describe associated remains of a larger marine reptile of around 4 m body length, with nothosauroidean affinities from the Sulphur Mountain Formation exposed at the L cirque locality of Wapiti Lake area in British Columbia. Although the specimen records only scattered parts of the posterior vertebral column, some gastral ribs and most notably, the proximal portion of one hind limb together with a fan-shaped ischium, it represents one of the oldest records of Sauropterygia and larger representatives of aff. Nothosauroidea specifically, as well as the northernmost occurrence of such animals in the Triassic. As such, the new specimen is important for understanding the biogeography and early evolution of the group and that of Sauropterygia, in general. [ABSTRACT FROM AUTHOR]

Fossil turtles are one of the least studied clades in regard to endocranial anatomy. Recently, the use of non-invasive technologies, such as radiographic computed tomography (CT), increased the knowledge of the neuroanatomy of several extinct and extant taxa. Here, we provide the description of the nasal cavity, cranial endocast, and inner ear of the stem turtle Naomichelys speciosa based on digital 3D reconstructions. This terrestrial form is characterized by a nasal cavity with anteroposteriorly elongated vestibulum and a large cavum nasi proprium, traits typically related to terrestrial habits. The large olfactory region of the cavum nasi proprium suggests that olfaction was probably the most important sense for this species. Our description of N. speciosa adds novel information to the knowledge of endocranial anatomy in early turtle evolution and provides an important foundation for future analyses and comparisons. [ABSTRACT FROM AUTHOR]

Khurendukhosaurus is an enigmatic genus of choristodere, recorded from the Lower Cretaceous of East Asia, Mongolia, and Siberian Russia. Until now, it was known only from isolated skull and postcranial elements, limiting comparison with other genera. Three major morphotypes have been recognised within Choristodera: longirostrine neochoristoderes with short-necks, and brevirostrine non-neochoristoderes with either short or long necks. The morphotype of Khurendukhosaurus was uncertain, although it had been inferred to be long-necked, based on cervical and caudal vertebral morphology shared with the Chinese Hyphalosaurus and on the results of phylogenetic analysis that placed it within a clade of Sino-Japanese long-necked taxa. Newly discovered material from the Mongolian type locality, Khuren-Dukh, preserves most major postcranial elements of a single individual. This specimen confirms that Khurendukhosaurus belongs to the long-necked morphotype, in having at least 13 cervical vertebrae. Moreover, a new phylogenetic analysis supports the placement of Khurendukhosaurus as a sister group of the Hyphalosaurus + Shokawa clade. Based on the new material, Khurendukhosaurus is estimated to have been roughly 1 m in total length, placing it at the upper end of the size range for long-necked choristoderes. [ABSTRACT FROM AUTHOR]

This paper summarizes knowledge on the Neogene-Quaternary terrestrial fossil record from the Middle Kura Basin accumulated over a century and aims to its integration into the current research. This fossil evidence is essential in understanding the evolution of the Eurasian biome, since this territory is located at the border of Eastern Mediterranean and Central Asian regions. The general biostratigraphic framework suggests existence of two major intervals of the terrestrial fossil record in the area, spanning ca. 10-7 Ma and ca. 3-1 Ma, and points to an important hiatus between the late Miocene and late Pliocene. General aspects of the paleogeographic history and fossil record suggest that the biogeographic role of the Middle Kura Basin has been changing over geological time from a refugium (Khersonian) to a full-fledged part of the Greco-Iranian province (Meotian-Pontian). The dynamic environmental changes during the Quaternary do not depict this territory as a refugium in its general sense. The greatest value of this fossil record is the potential to understand a detailed history of terrestrial life during demise of late Miocene Hominoidea in Eurasia and early Homo dispersal out of Africa. Late Miocene record of the Middle Kura Basin captures the latest stage of the Eastern Paratethys regression, and among other fossils counts the latest and the easternmost occurence of dryopithecine, Udabnopithecus garedziensis, while the almost uninterrupted fossil record of the late Pliocene-Early Pleistocene covers the time interval of the early human occupation of Caucasus and Eurasia. [ABSTRACT FROM AUTHOR]

Three morphotypes of the fifth metatarsal (MttV), one of the most informative bones of the postcranium, have been described herein from the Early Triassic karst deposits of the Czatkowice locality (Southern Poland). Two of them have been assigned to a basal archosauriform Osmolskina czatkowicensis and a basal lepidosauromorph, Sophineta cracoviensis, respectively, while one is undetermined saurian. Two morphological categories of the hooked fifth metatarsals recognized from this assemblage account for two different solutions to the problem of improvement of locomotion. A strongly inflected (sensu Robinson 1975) MttV shaft consists of two parts, a distal one lying on the ground in a plantigrade manner and a proximal one bent at an angle to get align with the ventral surface of the crus and proximal tarsus. In contrast, a straight shaft of the hooked MttV, suggests its subvertical life position and thus a digitigrade foot stance. The hooking of the fifth metatarsal, that is currently accepted saurian synapomorphy, appeared in phylogeny in a primitive state referred to herein as a neckless type: with neither a neck-shaped articular protrusion for the fourth distal tarsal nor a directly medial orientation of the articular facet. A derived long-necked type with protruding arricular part and more directly medial orientation of the articular facet appeared, at various stages of further phylogeny. A strong plantar-dorsal inflexion of the fifth metatarsal associated with a protrusion of lateral plantar tubercle, dates from a directly pre-lepidosaurian stage of evolution. [ABSTRACT FROM AUTHOR]

Honania complicidentata and Tsiyuania simplicidentata are pareiasaur taxa based on material from the Shangshihezi Formation of Jiyuan, Henan Province, China that were earlier designated as nomina vana. Based on the study of new material, and the reexamination of old specimens, we determine that the pareiasaur material from Jiyuan represents a single species that differs from all known species from other localities. Thus, we resurrect the name H. complicidentata for the material from Jiyuan. H. complicidentata is characterized by maxillary teeth with high crowns, dentary teeth slightly posteriorly inclined compared to the dentary dorsal margin, nearly all preserved marginal teeth have a cusped cingulum on the lingual surface, and humerus without an ectepicondylar foramen. Phylogenetic analysis shows Honania is more basal than Shansisaurus and Shihtienfenia from the Sunjiagou Formation of China. [ABSTRACT FROM AUTHOR]

Central Asia is a key area for crocodylomorph evolution, lying midway between the highly documented deposits in Europe and North America, but crocodylomorph fossils from this part of the world are rare. Included among these are specimens collected in the 1970s and 1980s by the Soviet-Mongolian Expeditions in the Jurassic and Cretaceous of Mongolia, Tajikistan, and Kazakhstan. Three species, "Sunosuchus" shartegensis, Kansajsuchus extensus, and Turanosuchus aralensis are redescribed and subjected to phylogenetic analysis for the first time. "Sunosuchus" shartegensis and Kansajsuchus are relatively derived goniopholidids, and part of a pan-east-Laurasian radiation of goniopholidids from which the European goniopholidids subsequently radiated. No characters can be used to distinguish "Sunosuchus" shartegensis from "S." thailandicus; the two species are therefore synonymized. Turanosuchus aralensis is here considered a nomen dubium. Cladistic analysis suggests that Sunosuchus is polyphyletic, indicating a higher degree of diversification than was previously thought, but also pointing to the need for further systematic revision. [ABSTRACT FROM AUTHOR]

South American Mesozoic snake diversity is mostly represented by genera from the Cenomanian (Najash), Santonian--Campanian (Dinilysia), and Campanian--Maastrichtian (Alamitophis, Patagoniophis, Rionegrophis, and Australophis) of Patagonia, Argentina. In this paper, we describe a new snake genus and species, Seismophis septentrionalis, from the Cenomanian (early Late Cretaceous) of the Alcântara Formation, Maranhão, northeastern Brazil. The new snake comprises a posteriormost trunk vertebra and possibly a poorly preserved midtrunk vertebra. Both vertebrae share small size, zygosphene moderately thick with a rectilinear roof, absence of paracotylar foramina, presence of parazygantral foramina, and strongly marked parasagittal ridges of the neural arch. The new snake is here considered of uncertain systematic affinities, but probably close to the limbed snake Najash rionegrina. Although the material is very fragmentary and the systematic assignment is still unresolved, this snake represents the oldest, as well as probably the most primitive snake from Brazil. [ABSTRACT FROM AUTHOR]

Plesiosauria is a clade of medium to large bodied marine reptiles with a cosmopolitan distribution ranging from the latest Triassic to the end of the Cretaceous. In Europe, the fossil record of Plesiosauria is mainly known from the Northern latitudes, whereas it is much rarer from the Southern and Mediterranean areas. Here, we report the first articulated skeleton of an Italian plesiosaurian, from the Callovian--Oxfordian deposits of the Rosso Ammonitico Veronese Formation of Kaberlaba (Veneto). The specimen is referred to Pliosauridae based on the large size of the skull, compared to the appendicular skeleton, the presence of the lacrimal, and a distinct anterolateral projection of the prefrontal into the orbital margin. Mandibular and vertebral symplesiomorphies support the placement of the Italian taxon among the "gracile-lonirostrine grade" of basal pliosaurids. The Kaberlaba plesiosaurian represents the second reptile clade recovered from the Rosso Ammonitico Veronese Formation, after Thalattosuchia. [ABSTRACT FROM AUTHOR]

Two giant partial bone shafts, possible femora, from the Rhaetian Bone Bed (Upper Triassic) of Aust Cliff in SW England continue to conceal their origin. The most striking characteristic of these bones is their size, showing that dinosaur-like gigantism had already evolved by the Late Triassic. Based on their characteristic, columnar shaft morphology, it was previously suggested they came from a prosauropod or stegosaur. The bone histology of both specimens is very similar: the cortex is always rather thin, not exceeding 10 mm, and is of fibrolamellar type with longitudinal primary osteons. The primary osteons show a rather unusual feature, the development of a secondary osteon inside the primary one. The bone surface in both specimens shows open vascular canals, suggesting that the animals were still growing at the time of death, but an external fundamental system (EFS) is visible in the outermost cortex of specimen BRSMG Cb3870. The external cortex shows dense growth marks, but their annual nature is difficult to ascertain. The bones are probably dinosaurian, as indicated by the fibrolamellar bone, and possibly belong to an unknown basal sauropodomorph lineage. Alternatively, some very large pseudosuchians may have evolved fibrolamellar bone independently as an adaptation for reaching giant size. [ABSTRACT FROM AUTHOR]

Ichthyosaurs were highly adapted to a marine lifestyle, as shown by their fish-like body shape and their assumed active swimming abilities and high metabolic rates. However, the processes of adaptation to an aquatic life in the early stages of this lineage remain poorly understood. Here, we present the first osteohistological data concerning the most basal ichthyopterygian yet known, Utatsusaurus hataii, from the Lower Triassic of Japan. The cancellous bone structure suggests adaptation to active swimming in an open marine environment. Moreover, the possible occurrence of rapidly deposited bone tissue, in a fibrolamellar complex, suggests a higher metabolic rate than in modern poikilothermic reptiles, and therefore a trend toward homeothermy. This basal ichthyosaur, with its elongate body, was already more adapted to an aquatic lifestyle than expected from its morphology, and the process of adaptation to a marine lifestyle was already well advanced by the Early Triassic. [ABSTRACT FROM AUTHOR]

Complete plesiosaur skeletons are relatively abundant in the Lower Jurassic of England and Germany, but are exceptional in France. A new specimen from Normandy (northern France), including incomplete skull, palate and mandible with several associated vertebrae, is here described and its pliosauroid affinities are discussed. Comparison of this new specimen with other plesiosaurians indicates that it belongs to a new genus and species: Cryonectes neustriacus. This new plesiosaurian taxon represents one of the most complete pliosaurids reported from the Pliensbachian, a stage that has yielded very few diagnostic plesiosaurian remains. Our preliminary phylogenetic analysis places Cryonectes in a basal position among Pliosauridae, and suggests that the radiation of this clade occurred several millions of years earlier than previously thought. This new taxon contributes to our understanding of Early Jurassic plesiosaur diversity. [ABSTRACT FROM AUTHOR]

The extant venomous Gila monster and beaded lizards, species of Heloderma, live today in southwestern USA and south along the Pacific coastal region into Central America, but their fossil history is poorly understood. Here we report helodermatid osteoderms (dermal ossicles) from the late Miocene-early Pliocene Gray Fossil Site, eastern Tennessee USA. Twenty-three species of mammals are known from the fauna including abundant Tapirus polkensis, as well as fishes, anurans, salamanders, turtles, Alligator, birds, and snakes. Beaded lizards belong to the Monstersauria, a clade that includes Primaderma + Paraderma + Gobiderma + Helodermatidae (Estesia, Eurheloderma, Lowesaurus, and Heloderma). Osteoderms of lizards in this clade are unique within Squamata; they typically are circular to polygonal in outline, domed to flat-domed in cross-section, have a vermiculate surface texture, are not compound structures, and do not have imbricate surfaces as on many scincomorph and anguid lizards. We review and characterize the osteoderms of all members of Monstersauria. Osteoderms from the cranium, body, and limbs of Heloderma characteristically have a ring-extension (bony flange) at least partly surrounding the dome. Its presence appears to be a key character distinct to all species of Heloderma, consequently, we propose the presence of a ring-extension to be an apomorphy. Three osteoderms from the Gray Fossil Site range from 1.5 to 3.0 mm in diameter, have the circular shape of helodermatid osteoderms with a domed apical surface, and have the ring-extensions, permiting generic identification. Macrobotanical remains from the Gray Fossil Site indicate an oak-hickory subtropical forest dominated by Quercus (oak) and Carya (hickory) with some conifer species, an understorey including the climbing vines Sinomenium, Sargentodoxa, and Vitis. Plant and mammal remains indicate a strong Asian influence. [ABSTRACT FROM AUTHOR]