Recent research on early bats has shown that diversification began early in the Early Eocene. The diversity was the highest in Europe and India and composed of the families Onychonycteridae, Icaronycteridae, Archaeonycteridae, Palaeochiropterygidae, and Hassianycteridae. However, in Europe, the oldest species have all been described from Northern Europe with the exception of Archaeonycteris? praecursor from Silveirinha (MP7, Portugal). Here we present a new bat from La Borie (MP8+9, South France). It is the first early Eocene species from Southern Europe identified on a relatively complete dentition: about 40 isolated teeth and dentary fragments. The teeth are nyctalodont and characterized by: moderate sized canines; middle sized p4 with well-developed metaconid; wide m1-2 with very lingual hypoconulid and high entoconid; middle sized P4; M1-2 with deep ectoflexus, weak paraconule, weak to absent metaconule, centrocrista not joining the labial border; m3/M3 smaller than m1-2/M1-2. These characters indicate that this species belongs to the Archaeonycteridae and is close to Archaeonycteris. It differs from Archaeonycteris trigonodon from Messel (MP11, Germany), A. brailloni from Mutigny and Avenay (MP8+9, France), and Protonycteris gunnelli from Vastan (India) by being about 25 % smaller. It is similar in size to Archaeonycteris? praecursor, A? storchi from Vastan, and the new archaeonycterid from Meudon (MP7, France). It differs from A? storchi by smaller p4 and shallower dentary, and from the Meudon species by more lingual hypoconulid, higher entoconid, and longer postcristid. In fact, it is very similar to A? praecursor by the m2 with relatively high entoconid and long postcristid; the main difference being the hypoconulid that is a little more lingual. The latter character suggests a more advanced dilambdodonty than A? praecursor, which is in agreement with the ages of the two localities. Both species seem to belong to the same evolutionary lineage geographically restricted to Southern Europe.
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RBINS Staff Publications 2016
A new artiodactyl of moderate size, Rajouria gunnelli nov. gen., nov. sp., is described on the basis of several dentaries, maxillae and isolated teeth from the middle Eocene Subathu Group of the Kalakot area, Rajouri District, Jammu and Kashmir, India. Despite its general resemblance with the family Dichobunidae by the retention of a paraconid on m1-2 and a simple P4 where endocristids do not form an anterior loph, this taxon shares with Raoellidae two unambiguous characters: the presence of a hypoconid on p4, and an asymmetrical P4. The phylogenetic position of the new taxon within the Cetacea–Raoellidae clade is strongly supported by seven non ambiguous synapomorphies, among which a cristid obliqua on lower molars anteriorly pointing towards the postectoprotocristid, and a P3 with only two roots. The presence of a new basal raoellid in the middle Eocene Subathu Group sheds new light on the phylogeny and paleobiogeography of raoellid artiodactyls.
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RBINS Staff Publications 2021
We here describe a new gekkotan lizard from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climates of the past 66 million years (Myr). This new taxon, with an age of 56 Myr, together with indeterminate gekkotan material reported from Silveirinha (Portugal, MP 7) represent the oldest Cenozoic gekkotans known from Europe. Today gekkotan lizards are distributed worldwide in mainly warm temperate to tropical areas and the new gecko from Dormaal represents a thermophilic faunal element. Given the Palaeocene–Eocene thermal maximum at that time, the distribution of this group in such northern latitudes (above 50° North – the latitude of southern England) is not surprising. Although this new gekkotan is represented only by a frontal (further, dentaries and a mandibular fragment are described here as Gekkota indet. 1 and 2—at least two gekkotan species occurred in Dormaal), it provides a new record for squamate diversity from the earliest Eocene ‘greenhouse world’. Together with the Baltic amber gekkotan Yantarogekko balticus, they document the northern distribution of gekkotans in Europe during the Eocene. The increase in temperature during the early Eocene led to a rise in sea level, and many areas of Eurasia were submerged. Thus, the importance of this period is magnified by understanding future global climate change.
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RBINS Staff Publications 2022 OA
