The lower Eocene (Ypresian) Cambay Formation at Vastan Lignite Mine in Gujarat, western India, has yielded a rich vertebrate assemblage including the earliest modern mammals and oldest birds of the Indian subcontinent. Among the herpetological faunas, snakes, lizards and amphibians are abundant, but, strangely, lizards are only represented by agamids. Here we describe the agamid assemblage based on numerous, diverse and well-preserved dentaries, premaxillaries, and maxillaries. At least four taxa are present at Vastan. Vastanagama susanae is characterized by dentaries with a large symphyseal facet, three anterior pleurodont teeth followed by acrodont teeth presenting a main cusp bordered by two lateral crests; the teeth increase in size posteriorly toward the coronoid process. Tinosaurus indicus exhibits a subdental ridge between the tooth row and the Meckelian canal, pleurodont symphyseal teeth including one that can be caniniform, and acrodont and tricuspid posterior teeth with poorly differentiated lateral cusps. Two other taxa represent two new genera and species. The first taxon presents multicuspid acrodont teeth with the main cusp surrounded by two or three progressively smaller lateral cusps. The second taxon presents pleurodont anterior teeth followed by a few acrodont teeth and ending with three or four subacrodont teeth near the coronoid process. Our results confirm that Agamidae (assigned to the Acrodonta) is the only lizard group present at Vastan, whereas many other groups are already present in the Early Eocene on the other continents. Agamidae is considered to have had a Gondwanan origin, with 52 genera and 420 species of extant agamids known from Asia, Australia, Africa and a few from Southern Europe. The oldest occurrence of formally recognized Acrodonta is found in the Jurassic of India. Other fossil agamids are known in the Upper Paleocene of Kazakhstan, Paleocene and Eocene of China, Early Eocene of Europe, Eocene of North America, and Middle Eocene of Pakistan. The diversity of the agamids in India and the absence of other lizard groups at Vastan tentatively support the Out-of-India hypothesis for agamids.
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Early Oligocene mammals from Europe are not well known. In Belgium this interval (reference level MP 21) is represented by four coeval localities, Boutersem, Boutersem-TGV, Hoogbutsel and Hoeleden. Included in a vertebrate assemblage of 20+ mammalian genera, one bat, Quinetia misonnei, has been previously described from Hoogbutsel, based on four lower dentitions. Twenty new specimens of Quinetia were recently recovered from Boutersem-TGV including six upper molars, a humerus, and thirteen lower dentitions. These new specimens confirm that Quinetia is a plecotine vespertilionid and consequently represents the earliest known occurrence of this tribe. Additionally, twenty five other dental specimens document the presence of a larger vespertilionid from Boutersem-TGV. These specimens are assigned to Myotis based on the primitive 3.1.3.3 dental formula, the presence of a single-rooted p3, myotodont lower molars, a relatively high crowned lower canine with well-developed mesial and distolingual shelves, M1 and M2 lacking both paraconules and metalophs, protofossa of M1 and M2 open posteriorly, and M3 being relatively short. The Boutersem-TGV Myotis specimens represent the earliest known record of this extant genus. Only some isolated potential myotine teeth from Le Batut (MP 19) in France are older but these teeth differ from Myotis in having upper molars with a paraloph and a protofossa closed posteriorly, both features more typical of the enigmatic “Leuconoe”. Myotodont species, such as “L”. salodorensis from Oensingen (MP 25) in Switzerland and “L”. lavocati from Le Garouillas (MP 25-28) in France, both share features of upper teeth that distinguish them from Myotis. Younger still are three Myotis species from Herrlingen 8-9 (MP 29) in Germany. Compared to the Boutersem-TGV Myotis, M. minor is much smaller with a relatively smaller, shorter and more delicate p4, M. intermedius is somewhat smaller in molar dimensions but with a substantially smaller and shorter p4, while M. major has larger m1-2, similar sized m3, smaller p4, more robust M1 and a more constricted P4 lingual shelf. The origin of Myotis appears to be at least as old as the earliest Oligocene.
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