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We here describe Terastiodontosaurus marcelosanchezi , a new amphisbaenian genus and species from the Eocene of Chambi, Tunisia. Using micro-computed tomography (μCT), we document the peculiar anatomy of the new taxon, which is characterized by extreme dental morphology, including one massive tooth on the maxilla and dentary, flat cheek teeth, and an array of other diagnostic features that readily differentiate it from all other amphisbaenians. We also redescribe the oldest named African amphisbaenian, Todrasaurus gheerbranti , from the late Palaeocene of Morocco, using μCT. Phylogenetic analysis recovers Terastiodontosaurus and Todrasaurus as sister taxa and provides strong support for a sister-group relationship of those two large-toothed amphisbaenians with extant Trogonophis. Accordingly, Todrasaurus shows that the divergence of crown Trogonophidae occurred much earlier than currently thought. Our survey of μCT scans reveals that Terastiodontosaurus , Todrasaurus , and Trogonophis are characterized by a great enamel thickness on their teeth, a feature that is absent in other examined amphisbaenians. Size estimates show that Terastiodontosaurus was the largest known amphisbaenian ever to have lived, with an estimated skull length of >5 cm. Based on new muscle data of Trogonophis , we estimate very high bite forces for Terastiodontosaurus , which would allow it to crush a wide variety of snails. [ABSTRACT FROM AUTHOR]

We describe two exceptionally preserved fossil snakes from the Eocene Konservat-Lagerstätte of Geiseltal, located in the state of Saxony-Anhalt, Germany. The two snake specimens, GMH LIX-3-1992 and GMH XXXVIII-20-1964, can be confidently identified as booids based on general morphology and were thus compared to other geographically and/or temporally close fossil booids. We found that GMH LIX-3-1992 is morphologically very similar to Eoconstrictor spinifer , also from Geiseltal, and to Eoconstrictor fischeri , from the middle Eocene of Messel, but differs from both in a number of cranial and vertebral features. Based on these differences we erect the new species Eoconstrictor barnesi sp. nov. ; GMH XXXVIII-20-1964 is very similar to GMH LIX-3-1992 and the two differ only in features that are likely ontogenetic. Phylogenetic analyses of snakes using maximum parsimony and Bayesian inference on datasets inclusive of both morphological and molecular data consistently support a close affinity of E. barnesi to E. fischeri and E. spinifer. Our preferred phylogenetic hypothesis places the three species of Eoconstrictor in a clade that is sister to Neotropical Boidae, a result consistent with previous studies. The genus Eoconstrictor could provide an important calibration point for molecular clock studies of booids and snakes in general. [ABSTRACT FROM AUTHOR]

We here report an anterior trunk vertebra of a large snake that we tentatively refer to Palaeophis africanus. The vertebra comes from lower middle Eocene deposits of the El Breij Depression, in the Sahara Desert of southern Morocco. It is principally characterised by weak lateral compression; horizontality of the cotyle-condyle axis; dorsoventrally thick zygosphene; lower pterapophyses with an upper edge that remains lower than that of the zygosphene in lateral view; a rather reduced neural canal; very distinct and prominent interzygapophyseal crests; low position of the diapophyses; and the presence of two hypapophyses. This occurrence adds to the geographic distribution of Palaeophis africanus, which has been formerly identified from Nigeria, Togo, Angola, and South America, and represents an additional Palaeophis species for the Moroccan fossil record. [ABSTRACT FROM AUTHOR]

We report avian cervical vertebrae from the Quercy fissure fillings in France, which are densely covered with villi‐like tubercles. Two of these vertebrae stem from a late Eocene site, another lacks exact stratigraphic data. Similar cervical vertebrae occur in avian species from Eocene fossils sites in Germany and the United Kingdom, but the new fossils are the only three‐dimensionally preserved vertebrae with pronounced surface sculpturing. So far, the evolutionary significance of this highly bizarre morphology, which is unknown from extant birds, remained elusive, and even a pathological origin was considered. We note the occurrence of similar structures on the skull of the extant African rodent Lophiomys and detail that the tubercles represent true osteological features and characterize a distinctive clade of Eocene birds (Perplexicervicidae). Micro‐computed tomography (μCT) shows the tubercles to be associated with osteosclerosis of the cervical vertebrae, which have a very thick cortex and much fewer trabecles and pneumatic spaces than the cervicals of most extant birds aside from some specialized divers. This unusual morphology is likely to have served for strengthening the vertebral spine in the neck region, and we hypothesize that it represents an anti‐predator adaptation against the craniocervical killing bite ("neck bite") that evolved in some groups of mammalian predators. Tuberculate vertebrae are only known from the Eocene of Central Europe, which featured a low predation pressure on birds during that geological epoch, as is evidenced by high numbers of flightless avian species. Strengthening of the cranialmost neck vertebrae would have mitigated attacks by smaller predators with weak bite forces, and we interpret these vertebral specializations as the first evidence of "internal bony armor" in birds. [ABSTRACT FROM AUTHOR]

We present new disarticulated cranial elements of the Eocene frog Thaumastosaurus from several localities in the Phosphorites du Quercy, France, providing novel information about the variation of its anatomical characteristics. With the use of micro-computed tomography (μCT) scanning technology, we examine and discuss various types of dermal cranial ornamentation in extant Pyxicephalus , the closest extant relative of Thaumastosaurus , in which these features are useful in species diagnoses, paying particular attention to the individual and ontogenetic variation, and sexual dimorphism, as well as interspecific variation among extant species. We suggest that various types of dermal cranial ornamentation in Thaumastosaurus could be potentially used in diagnoses at species level, although ontogenetic variation should be taken into consideration. Apart from ornamentation, the size and general morphology of the maxillae and squamosa in Thaumastosaurus reveal an unexpected disparity of morphotypes, which suggests the potential presence of cryptic taxa. Some squamosa reveal that their processus zygomaticus extended up to the postnasal wall, so their associated maxillae were excluded from the orbital margin, whereas others were short and their respective maxillae participated in the formation of the orbital margin. Thaumastosaurus is envisaged as the product of an Early Palaeogene direct, potentially overseas, dispersal from isolated Afro-Arabia to Europe. [ABSTRACT FROM AUTHOR]

We review in detail the published fossil record of turtles from Sardinia and, in addition, we document previously undescribed specimens for the first time. Among these undescribed specimens, is the oldest occurrence of Testudo hermanni on the island, from the Early Pleistocene of Monte Tuttavista. The turtle fossil record in Sardinia goes back to the Eocene and comprises 18 different taxa, pertaining to 6 lineages: Podocnemididae, Cheloniidae, Emydidae, Geoemydidae, Testudinidae, and Trionychidae. Remarkable is the occurrence of Eocene pleurodires, whose presence is in agreement with the Oligo-Miocene rifting of the Corso-Sardinian block. Interestingly, the fossil record provides evidence for the presence in the island of both Testudo hermanni and Emys orbicularis during the Pleistocene although according to molecular data the extant populations of these two taxa were introduced in recent times. Finally, a large ungual phalanx from the Middle–Late Pleistocene Monte San Giovanni bone breccia testifies the occurrence of a giant tortoise in the Quaternary terrestrial ecosystem of Sardinia. [ABSTRACT FROM AUTHOR]

Archaeological investigations carried out in the cave Zubbio di Cozzo San Pietro, Bagheria, Sicily, revealed the presence of a few skeletal elements of a large-sized tortoise in a funerary area dating to the Copper/Bronze Age. The tortoise has been AMS-dated revealing an age of 12.5 ± 0.5 kyr BP and therefore it pre-dates the funerary activities. The morphology of the retrieved skeletal elements differs from that of the only native tortoise currently living in Sicily, Testudo hermanni. The tortoise's size significantly exceeds the size range of extant Te. hermanni and all Testudo spp. as well as that of their known fossils, and suggests a shell length of 50–60 cm. Repeated efforts to obtain DNA sequences from the tortoise of Zubbio di Cozzo San Pietro failed, but the morphology of the femur is distinct enough to allow us to erect a new taxon, Solitudo sicula gen. et sp. nov. , based on a parsimony analysis. It belongs to a hitherto unrecognized clade that includes other large-sized tortoises from Mediterranean islands, like Malta and Menorca. A review of the pertinent taxa indicates that the remains here described represent the geologically youngest large-sized tortoise of the Mediterranean area. [ABSTRACT FROM AUTHOR]

We here describe fossil remains from three Lower and Middle Miocene localities of Anatolia, which we tentatively refer to chamaeleonids. The material comprises isolated tooth-bearing bones from the Early Miocene (MN 3) of Sabuncubeli (western Anatolia), the Early Miocene (MN 4) of Dededağ (western Anatolia), and the Middle Miocene (MN 5) of the world-renowned hominoid locality of Paşalar (northwestern Anatolia). If our identifications are correct, these specimens would represent the only fossil record of this group from Anatolia as well as the oldest occurrences of chameleons from Asia. Moreover, the recovery of these specimens across different Lower and Middle Miocene localities, suggest that these animals were a typical element of the Anatolian herpetofaunas of the early Neogene. Differences among the specimens from the three localities point to a higher taxonomic diversity of Miocene Anatolian chamaeleonids, however, based on such limited material, intraspecific or ontogenetic variation cannot be ruled out. The oldest among these occurrences, the Sabuncubeli material, coincides chronologically with the oldest chameleons, which had been previously described from Central Europe (MN 3). As such, this supports the recently suggested biogeographic scenario, according to which chamaeleonids dispersed from Afro-Arabia to Europe during the Burdigalian, via the "Gomphotherium Landbridge," through Anatolia and the Balkans. Finally, a few additional lizard and snake remains from the locality of Dededağ are described, adding to the poorly known fossil herpetofaunas of Anatolia. [ABSTRACT FROM AUTHOR]

Herein, we revise the material of the extinct taxon Pseudopus pannonicus from Central Europe, the largest known anguid lizard and iconic member of herpetofaunas from the Upper Cenozoic of Europe. The geographical position of Polgárdi 2, the type locality of P. pannonicus, as well as several other closely located important localities make Central Europe a valuable area of high interest for studies regarding European Cenozoic palaeoherpetological assemblages. We clarified the nature of the type material of Pseudopus pannonicus, showing that it consisted not only of the five specimens originally figured. Instead, the syntype series also includes a considerable number of specimens from Polgárdi 2 that were only described or figured 12 years after the original description of P. pannonicus. Detailed osteological descriptions are provided for specimens from the type series and Polish specimens, with the aid of high-resolution imaging (SEM and μCT scanning), and intraspecific variability is discussed. The articular surface with the lappet of the parietal overlapping the frontal is discussed as a character potentially relevant for the diagnosis of P. pannonicus. We updated the identification of several specimens of P. pannonicus and discussed the biogeographic implications of such revisions. In Poland, P. pannonicus is an abundant component of Neogene and early Quaternary herpetofaunas, known with certainty from the Middle Miocene of Przeworno (the oldest known occurrence of the species globally), the Early-Late Pliocene of Węże I, the Late Pliocene of Rębielice Królewskie I, the Late Pliocene of Węże II, and the Early Pleistocene of Kadzielnia (one of the youngest occurrences documented globally). An indeterminate anguine with Anguis affinities is newly reported from Rębielice Królewskie II. The taxonomic status of other large anguids from the Neogene of Europe is discussed and we conclude that most are junior synonyms of P. pannonicus. We also show that another purported synonym, that is, Ophisaurus intermedius from the Early Pleistocene of Romania, is instead a nomen nudum. We conducted phylogenetic analyses (18 taxa, 65 characters) to understand the relationship of P. pannonicus relative to other anguid representatives and anguid-related group (i.e., glyptosaurids). A single most parsimonious tree (length: 134 steps) was recovered. The clade Pseudopus is stable, comprising the two distinct sister subclades [Pseudopus laurillardi + Pseudopus ahnikoviensis] and [Pseudopus pannonicus + Pseudopus apodus]. These phylogenetic results are in accordance with previously published works., (© 2024 American Association for Anatomy.)

We here provide a detailed description of the vertebral morphology of the African arboreal viperid snakes of the genus Atheris. Vertebrae of three different species of the genus, i.e., Atheris desaixi, Atheris hispida, and Atheris katangensis, were investigated via the aid of μCT (micro-computed tomography) scanning. We describe several vertebrae from different regions of the vertebral column for all three species, starting from the atlas-axis complex to the caudal tip, in order to demonstrate important differences regarding the intracolumnar variation. Comparison of these three species shows an overall similar general morphology of the trunk vertebrae among the Atheris species. We extensively compare Atheris with other known viperids. As the sole arboreal genus of Viperinae the prehensile nature of the tail of Atheris is reflected in its caudal vertebral morphology, which is characterized by a high number of caudal vertebrae but also robust and anteroventrally oriented pleurapophyses as a skeletal adaptation, linked with the myology of the tail, to an arboreal lifestyle. We anticipate that the extensive figuring of these viperid specimens will also aid identifications in paleontology., (© 2024 American Association for Anatomy.)

We here describe abundant new snake material from the late Miocene (MN 13) of Salobreña, Spain. Vertebral morphology suggests a referral of the specimens to the extant psammophiid Psammophis, documenting the first occurrence of this genus in Europe. The diversity and disparity across the vertebral morphology of different psammophiid genera are discussed. We identify vertebral features that could diagnose Psammophis and therefore enable the recognition of the genus in the fossil record. A comparison of the new Spanish form with other taxa is conducted. We provide a detailed review of the psammophiid fossil record. Material previously described from the middle Miocene of Beni Mellal, Morocco is here tentatively referred to as ?Psammophis sp., an action that renders that occurrence as the oldest (probable) record of the genus and Psammophiidae as a whole, providing thus a potential calibration point. On the other hand, Eastern European Pliocene material that had been previously supposedly referred to Psammophis is here discarded as being rather fragmentary, not affording any more precise determination. The two psammophiid genera Psammophis and Malpolon appear almost simultaneously in the European fossil record (MN 13), with the former achieving only a short-lived and apparently geographically limited distribution in the continent, while the latter still exists in its modern herpetofauna. We assess biogeographic implications of the new find, suggesting a direct dispersal event from northwestern Africa to the Iberian Peninsula during the late Miocene, facilitated by the Messinian Salinity Crisis., (© 2022 American Association for Anatomy.)