The taxonomic status of the kukri snake Oligodon arenarius Vassilieva, 2015 with a redescription of Oligodon macrurus (Angel, 1927) (Squamata, Serpentes, Colubridae)

We investigated the taxonomic status of the recently described kukri snake Oligodon arenarius Vassilieva, 2015 and the morphologically similar Oligodon macrurus (Angel, 1927), two species endemic to the southern coast of Vietnam. Based on phylogenetic analyses using three mitochondrial genes (12S–16S rRNA, cytochrome b), we recovered O. arenarius and O. macrurus in a clade within the O. cyclurus-taeniatus species group, agreeing with previous intrageneric classifications. Genetic distances between O. arenarius and O. macrurus are extremely low (less than 0.5% based on 12S–16S) and render O. arenarius paraphyletic. All preserved specimens of O. arenarius and O. macrurus convey little to no differences in color pattern, hemipenial morphology and osteological features; the latter of which is based on three dimensional micro computer tomography (µCT) scans of one specimen per species. Contrasting these results, univariate and multivariate analyses revealed significant differences in relative tail length, and the number of ventral and subcaudal scales between both species. Although the molecular and morphological datasets present conflicting results, integrating the evidence leads us to synonymize O. arenarius with O. macrurus. We provide a formal redescription of O. macrurus, designate a neotype specimen to avoid future taxonomic confusion, and provide the first detailed osteological description of this species. Oligodon macrurus sensu stricto is endemic to coastal dunefields and adjacent forest habitats in southern Vietnam, where ongoing human development, tourism and road mortality pose significant threats to its conservation. Consequently, we suggest that O. macrurus should be listed as “Vulnerable” based on the assessment criteria of the International Union for Conservation of Nature (IUCN)

The first Miocene fossils of Lacerta cf. trilineata (Squamata, Lacertidae) with a comparative study of the main cranial osteological differences in green lizards and their relatives.

We here describe the first fossil remains of a green lizard of the Lacerta group from the late Miocene (MN 13) of the Solnechnodolsk locality in southern European Russia. This region of Europe is crucial for our understanding of the paleobiogeography and evolution of these middle-sized lizards. Although this clade has a broad geographical distribution across the continent today, its presence in the fossil record has only rarely been reported. In contrast to that, the material described here is abundant, consists of a premaxilla, maxillae, frontals, parietals, jugals, quadrate, pterygoids, dentaries and vertebrae. The comparison of these elements to all extant green lizard species shows that these fossils are indistinguishable from Lacerta trilineata. Thus, they form the first potential evidence of the occurrence of this species in the Miocene. This may be also used as a potential calibration point for further studies. Together with other lizard fossils, Solnechnodolsk shows an interesting combination of survivors and the dawn of modern species. This locality provides important evidence for the transition of an archaic Miocene world to the modern diversity of lizards in Europe. In addition, this article represents a contribution to the knowledge of the comparative osteological anatomy of the selected cranial elements in lacertids. This study gives special emphasis to the green lizards, but new data are also presented for related taxa, e.g., Timon lepidus, Podarcis muralis or Zootoca vivipara. Although the green lizards include several cryptic species for which determination based on isolated osteological material would be expected to be difficult, our comparisons show several important morphological differences, although a high degree of variability is present

The easternmost record of the largest anguine lizard that has ever lived – Pseudopus pannonicus (Squamata, Anguidae): new fossils from the late Neogene of Eastern Europe

We here report on new material of Pseudopus pannonicus, the iconic and largest-known representative of the lizard clade Anguinae, from several late Neogene localities across Moldova, Ukraine, and regions of the North Caucasus – the last representing the easternmost known occurrence of this extinct species. Today, Pseudopus apodus, the last extant Pseudopus representative, is found in a variety of habitats ranging from South-East Europe to Central Asia. In the late Cenozoic of Europe, however, several extinct species of Pseudopus existed. Among them, interestingly, P. pannonicus displayed the largest spatiotemporal range of the genus, occurring from Spain to the North Caucasus and known from the Late Miocene to the Early Pleistocene. Although it has been reported in a plethora of European localities, P. pannonicus is a taxon “with several questionings related to its few diagnostic features vs. numerous features shared with P. apodus”. The elements described here exhibit some variability, but their overall morphology undoubtedly resembles that of previously described material of P. pannonicus. The lacrimal from Tatareshty, moreover, represents the first fossil lacrimal reported for P. pannonicus. Besides, the fairly complete maxilla with a length of almost 3.7 cm is the largest maxilla ever reported for this taxon, expanding our knowledge of its gigantism. In addition, several features are described and discussed regarding their diagnostic relevance for P. pannonicus. The relationship between body size and some of these features was tested statistically. Consequently, two cranial characters and one vertebral feature peculiar to P. pannonicus were retained in the diagnosis of the species

A NEW EARLY MIOCENE HERPETOFAUNA FROM KILCAK, TURKEY

###EgeUn###The fauna of amphibians and reptiles (except turtles) from the early Miocene localities of the Kilcak section (Turkey) is described here. The herpetofaunal assemblage of the Kilcak localities is the best documented early Miocene herpetofauna in Anatolia. The following taxa are revealed: Salamandra sp., Latonia sp., Eopelobates sp., Crocodylia indet., Lacertidae indet. (morphotypes A and B), Ophisaurus sp., Anguinae indet., Eoanilius cf. oligocenicus, Bavarioboa sp., Falseryx sp., and Texasophis sp. Among them, Latonia represents the oldest published record of this frog in Anatolia. Its maxilla is sculptured, extending the occurrence of the Latonia lineage with ornamented maxillae to the earliest Miocene, and demonstrating the long coexistence of the Latonia lineages (with smooth and ornamented maxillae), for almost the entirety of the Late Cenozoic. The genera Eopelobates, Eoanilius, and Falseryx are described from Anatolia and Asia for the first time. The booid fauna, being poorly known from this time interval (i.e., the so called "Dark Period" of booid snakes), significantly adds to our knowledge of early Miocene snake assemblages. The snake material from Kilcak indicates a transition from "ancient" late Oligocene to "modern" early-middle Miocene fauna. The widely distributed European taxa recovered in Kilcak, indicate that Anatolia had close faunal links to Europe during the late Oligocene - early Miocene.Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [19-04-00514, AAAA-A19-119020590095-9]; Ege UniversityEge University [TTM /001/2016, TTM/002/2016]; international bilateral research of TUBITAK-RFBRTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [111Y192]; University of Torino [SYNTHESYS ES-TAF-5910, SYNTHESYS AT-TAF-5911, SYNTHESYS HU-TAF-6145]; National Scholarship Program of the Slovak Republic (SAIA)Roman Rakitov (Borissiak Paleontological Institute RAS, Moscow, Russia) is thanked for assistance with SEM microscopy. Alexey Tesakov (Geological Institute of the Russian Academy of Sciences) and Andrej Eeroansky (Comenius University in Bratislava) are thanked for fruitful comments. Lars van den Hoek Ostende (Naturalis Biodiversity Center) is thanked for providing literature. This work was supported by the Russian Foundation for Basic Research under No. 19-04-00514, and the government theme under No. AAAA-A19-119020590095-9 (EVS). Authors also were supported by Ege University (TTM /001/2016) and (TTM/002/2016) research grants as well as the international bilateral research of TUBITAK-RFBR 111Y192 during his visits in Russia. GLG acknowledges travel support from the University of Torino, SYNTHESYS ES-TAF-5910 (MNCN, Museo Nacional de Ciencias Naturales, Madrid, Spain), SYNTHESYS AT-TAF-5911 (NHMW, Naturhistorisches Museum Wien, Vienna, Austria), and SYNTHESYS HU-TAF-6145 (HNHM, Hungarian Museum of Natural History, Budapest, Hungary) and funding from the National Scholarship Program of the Slovak Republic (SAIA)-the curators of MNCN, NHMW, and HNHM (Marta Calvo Revuelta, Heinz Grillitsch and Silke Schweiger, and Judit Voros, respectively) are highly acknowledged. We thank two anonymous reviewers for their comments and corrections

The taxonomic status of the kukri snake Oligodon arenarius Vassilieva, 2015 with a redescription of Oligodon macrurus (Angel, 1927) (Squamata, Serpentes, Colubridae)

We investigated the taxonomic status of the recently described kukri snake Oligodon arenarius Vassilieva, 2015 and the morphologically similar Oligodon macrurus (Angel, 1927), two species endemic to the southern coast of Vietnam. Based on phylogenetic analyses using three mitochondrial genes (12S–16S rRNA, cytochrome b), we recovered O. arenarius and O. macrurus in a clade within the O. cyclurus-taeniatus species group, agreeing with previous intrageneric classifications. Genetic distances between O. arenarius and O. macrurus are extremely low (less than 0.5% based on 12S–16S) and render O. arenarius paraphyletic. All preserved specimens of O. arenarius and O. macrurus convey little to no differences in color pattern, hemipenial morphology and osteological features; the latter of which is based on three dimensional micro computer tomography (µCT) scans of one specimen per species. Contrasting these results, univariate and multivariate analyses revealed significant differences in relative tail length, and the number of ventral and subcaudal scales between both species. Although the molecular and morphological datasets present conflicting results, integrating the evidence leads us to synonymize O. arenarius with O. macrurus. We provide a formal redescription of O. macrurus, designate a neotype specimen to avoid future taxonomic confusion, and provide the first detailed osteological description of this species. Oligodon macrurus sensu stricto is endemic to coastal dunefields and adjacent forest habitats in southern Vietnam, where ongoing human development, tourism and road mortality pose significant threats to its conservation. Consequently, we suggest that O. macrurus should be listed as "Vulnerable" based on the assessment criteria of the International Union for Conservation of Nature (IUCN)