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

Abstract

Serravallian terrestrial vertebrates are very uncommon in the northern margin of the Pyrenean Mountains. A mandible of a new large sized amphicyonid (ca. 200 kg) is here described from the marine deposits of Sallepisse (12.8–12.0 Mya). Despite that this new taxon is close in size to some European amphicyonids from the Miocene (e.g., Amphicyon, Megamphicyon, and Magericyon), the unique morphology of its p4, unknown in this clade, allows the erection of the new genus Tartarocyon cazanavei nov. gen. & sp. This taxon may be derived from a Cynelos-type amphicyonine. The description of this new taxon highlights the erosion of the ecological and morphological diversity of the Amphicyonidae in response to well-known Miocene events (i.e., Proboscidean Datum Event, Middle Miocene Climatic Transition, Vallesian Crisis).

Bear or bear-dog? An enigmatic arctoid carnivoran from the late Eocene of Asia

“…The ratio of m2 length to m1 length is 0.63 in Lonchocyon (Figure 4C), similar to the ratios in early thaumastocyonine Ysengrini (Crassidia and Ysengrinia) (0.58-0.62) but greater than the more derived Thaumastocyonini (0.37-0.54) (Solé et al, 2022). Furthermore, the talonid of m2 is shorter and narrower than the trigonid in the earliest thaumastocyonine Y. tolosana from the late Oligocene, but the talonid alveolus is slightly wider than the trigonid alveolus in Lonchocyon.…”

“…Furthermore, the talonid of m2 is shorter and narrower than the trigonid in the earliest thaumastocyonine Y. tolosana from the late Oligocene, but the talonid alveolus is slightly wider than the trigonid alveolus in Lonchocyon. Among the three tribes in Amphicyoninae, the ratio of m2 length to m1 length in Lonchocyon is close to those of Amphicyonini (0.63-0.71), Pseudocyon (0.6, 0.64), and Pseudarctini Dehmicyon schlosseria (0.59), greater than that of the Magericyonini Magericyon (0.45, 0.54) and lesser than that of the Pseudarctini Ictiocyon (0.72) and Pseudarctos (0.71) (Morales et al, 2021b;Solé et al, 2022). The early amphicyonine Pseudocyonopsis from the Oligocene to early Miocene has a similar ratio between m2 length to m1 length (0.59, 0.61) to Lonchocyon (Kuss, 1965).…”

“…The p4 of Lonchocyon is characterized by its rather small size with two fused roots and a small posterior shelf, as well as the lack of a posterior accessory cuspid. The length ratio of p4 to m1 is 0.31 in Lonchocyon (Figure 4A), which is less than the ratio in Magericyon (0.38, 0.42), while the ratios in other genera of amphicyonines (0.44-0.67) and thaumastocyoninae (0.48-0.71) are usually much greater (Solé et al, 2022). The ratio of p4 to m1 length in the ursine Ballusia and Ursavus ranges from 0.44 to 0.61 (Qiu et al, 2014), and the ratio in Ursus minimus ranges from 0.45 to 0.59 (Baryshnikov and Lavrov, 2013).…”

Nouvelles données géologiques et biostratigraphiques du gisement paléontologique à vertébrés de Mauvières, à Marcilly-sur-Maulne (Miocène inférieur et moyen; Indre-et-Loire, France)

“…Les données biostratigraphiques proviennent de la littérature. Lagomorpha , Lagopsis cadeoti (Viret, 1930): Hugueney & Bulot 2011; Prolagus vascociensis (Viret, 1930): Boon-Kristkoiz & Kristkoiz 1999; Amphilagus ulmensis (Tobien, 1963): Angelone 2009; Rodentia , Eucricetodon infralactorensis (Viret, 1930): Hugueney 1999a; Steneofiber depereti Mayet, 1908: Hugueney 1999b; Carnivora , Megamphicyon carnutense (Antunes & Ginsburg, 1977): Solé et al 2022; Cynelos helbingi (Dehm, 1950): Solé et al 2022; Ballusia hareni (Ginsburg, 1989): Ginsburg & Morales 1998, Baryshnikov & Lavrov 2015; Phoberocyon aurelianensis (Mayet, 1908): Ginsburg & Morales 1998; Phoberocyon dehmi (Ginsburg, 1955): Ginsburg & Morales 1998; Plithocyon bruneti Ginsburg, 1980: Ginsburg & Morales 1998; Hemicyon gargan Ginsburg & Morales, 1998: Ginsburg & Morales 1998; ursavus isori Ginsburg & Morales, 1998: Ginsburg & Morales 1998; Plesiogale angustifrons Pomel, 1854: Ginsburg 2001; Martes laevidens Dehm, 1950: Ginsburg et al 2000, Ginsburg 2001; Semigenetta elegans Dehm, 1950: Kargopoulos et al 2021; Broiliana nobilis Dehm, 1950: Ginsburg 2001; Stromeriella franconica Dehm, 1950: Ginsburg 2001; Styriofelis turnauensis Hoernes, 1882: Robles et al 2013; Perissodactyla , Paratapirus intermedius (Filhol, 1885): Scherler et al 2011; Protaceratherium minutum (Cuvier, 1822): Antoine & Becker 2013; Diaceratherium aurelianense (Nouel, 1866): Becker et al 2009, Scherler et al 2011; Plesiaceratherium sp. (Mermier, 1895): Antoine et al 2000; Artiodactyla , Aureliachoerus aurelianensis (Stehlin, 1899): Scherler et al 2013; Xenohyus venitor Ginsburg, 1980: Bouvrain & Bonis 1999; Brachyodus intermedius Mayet, 1908: Orliac et al 2013; Cainotherium lintillae Baudelot & Grouzel, 1974: Berthet 2003; Palaeomeryx kaupi Meyer, 1834: Ginsburg 1985; Andegameryx andegaviensis Ginsburg, 1971: Ginsburg 1999a, Mennecart et al 2016; Andegameryx serum (Ginsburg, 1999): Ginsburg 1999a; Amphimoschus cf.…”