A New Thaumastocyoninae (Amphicyonidae, Carnivora) from the Early Miocene of Tuchořice, the Czech Republic

Abstract

<jats:title>Abstract</jats:title> <jats:p>New Amphicyonidae fossil remains from the early Miocene site of Tuchořice (the Czech Republic) confirm the presence of a new Thaumastocyoninae taxon: <jats:italic>Peignecyon felinoides</jats:italic> n. gen. et n. sp. It is characterized by a peculiar combination of plesiomorphic and derived morphological traits. The new genus can be defined by a long and sharp mandible diastema, loss of mesial premolars (p2–p3), p4 with an inclined distally high main cuspid, moderate sectorial carnassial teeth, m1 with relict metaconid, and talonid and trigonid of similar width, and reduced M2 and m2. In the phylogenetic analysis the Thaumastocyoninae form a monophyletic group characterized by the start of the m2/M2 reduction, still moderate in <jats:italic>Crassidia intermedia</jats:italic> (<jats:sc>von</jats:sc> M<jats:sc>eyer</jats:sc>, 1849), but remarkable in the other species of the clade. <jats:italic>Peignecyon felinoides</jats:italic> already shows the advanced features defining the Thaumastocyoninae, and constitutes the sister group of the most specialized genera <jats:italic>Tomocyon</jats:italic> V<jats:sc>iret</jats:sc>, 1929b and <jats:italic>Thaumastocyon</jats:italic> S<jats:sc>thelin</jats:sc> et H<jats:sc>elbing</jats:sc>, 1925. Consequently, it can be considered an excellent link between this group and the more primitive members of the tribe Ysengrini (<jats:italic>Ysengrinia</jats:italic> G<jats:sc>insburg</jats:sc>, 1966 and <jats:italic>Crassidia</jats:italic> H<jats:sc>eizmannn</jats:sc> et K<jats:sc>ordikova</jats:sc>, 2000). <jats:italic>Peignecyon felinoides</jats:italic> shows that the trend towards hypercarnivory had already emerged in the European early Miocene fauna, thus helping to understand the complex evolution of the Amphicyonidae during the Miocene.</jats:p>

A new gigantic carnivore (Carnivora, Amphicyonidae) from the late middle Miocene of France

“…Because of the lack of information on the morphology of the molars, it is hard to discuss the relationships of Tartarocyon cazanavei nov. gen. & sp. within the amphicyonids; the molars actually provide numerous diagnostic features (see for instance the diagnoses in Kuss, 1965 ; Viranta, 1996 ; Heizmann & Kordikova, 2000 ; Peigné & Heizmann, 2003 ; Peigné et al, 2008 ; Morales et al, 2019 ; Morales et al, 2021a ; Morales et al., 2021b ). Viranta (1996) , Peigné et al (2008) , Morales et al (2019) , Morales et al (2021a) and Morales et al.…”

“…within the amphicyonids; the molars actually provide numerous diagnostic features (see for instance the diagnoses in Kuss, 1965 ; Viranta, 1996 ; Heizmann & Kordikova, 2000 ; Peigné & Heizmann, 2003 ; Peigné et al, 2008 ; Morales et al, 2019 ; Morales et al, 2021a ; Morales et al., 2021b ). Viranta (1996) , Peigné et al (2008) , Morales et al (2019) , Morales et al (2021a) and Morales et al. (2021b) tackled the relationships among European amphicyonids.…”

“…The youngest thaumastocyonine species, from the middle and late Miocene, are further characterized by the absence of m3 and of p1, p2, and p3, and a leaning backward main cuspid on p4 ( Fig. 4 , Table 3 ) ( Morales et al, 2019 ; Morales et al, 2021a ; Morlo et al, 2020 ). A reduction of premolar size is also observed in amphicyonines; this is a common trend in European amphicyonids.…”

“…Among these genera, only Gobicyon is known from Europe ( G. serbiae in MN6; Pavlovic & Thenius, 1959 ; Ginsburg, 1999 ; Jiangzuo et al, 2018 ). The Thaumastocyoninae groups the genera Thaumastocyon , Ysengrinia , Tomocyon , Crassidia , Agnotherium , Ammitocyon , and possibly Amphicyonopsis ( Morales et al, 2019 ; Morales et al, 2021a ; Morales et al., 2021b ; Morlo et al, 2020 ). The Amphicyoninae as defined by Peigné et al (2008) is now considered to probably be paraphyletic, forming a grade and including several lineages more basal than the thaumastocyonines or included in this subfamily ( Morales et al, 2019 ; Morales et al, 2021a ; Morales et al., 2021b ).…”

“…The Thaumastocyoninae groups the genera Thaumastocyon , Ysengrinia , Tomocyon , Crassidia , Agnotherium , Ammitocyon , and possibly Amphicyonopsis ( Morales et al, 2019 ; Morales et al, 2021a ; Morales et al., 2021b ; Morlo et al, 2020 ). The Amphicyoninae as defined by Peigné et al (2008) is now considered to probably be paraphyletic, forming a grade and including several lineages more basal than the thaumastocyonines or included in this subfamily ( Morales et al, 2019 ; Morales et al, 2021a ; Morales et al., 2021b ). Morales et al (2021b) created two new tribes (Pseudarctini and Magericyonini) to clarify the systematics of Miocene amphicyonines.…”