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| Tartarocyon cazanavei Solé, Lesport, Heitz & Mennecart, 2022 |
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).
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| Holotype (MHNBx 2020.20.1) of Tartarocyon cazanavei nov. gen. et sp. from Sallespisse (MN7/8, Southwest France), in occlusal, lingual, and labial views. Scale bar is 5 cm. |
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| Reconstruction of Tartarocyon cazanavei nov. gen. et sp. feeding on a stranded dolphin along the Serravallian sea. We know only few on the inland environmental conditions where Tartarocyon lived. This illustration thus combines all the data from the site la Crousquillière in Sallespisse including the intertidal dark deposits, the abundance of the molluscs, and the mandible of Tartarocyon in the high-tide line. Drawing by Denny Navarra. |
Order CARNIVORA Bowdich, 1821
Suborder CANIFORMIA Kretzoi, 1943
Family Amphicyonidae Trouessart, 1885
Tribe Amphicyonini Trouessart, 1885
Genus Tartarocyon nov. gen.
Etymology. Tartaro is the name of a legendary man-eater giant living in the Southwestern French Pyrenees, including the Bearn where the fossil has first been described. –cyon is the Greek for dog.
Tartarocyon cazanavei nov. gen. et sp.
Etymology. Dedicated to Mr Alain Cazanave, owner of the locality, who helped with the excavation during many years.
Diagnosis. Large size Amphicyoninae possessing a complete dental formula. The taxon is characterized by the following features: long diastemata between the premolars, low p2 and p3, absent anterior accessory cuspid on p4, large and individualized distal accessory cuspid on p4, and unreduced m2 and m3. The taxon differs from all the European amphicyonids from the Miocene by the individualization of the distal accessory cuspid from the main cuspid on p4 and the extreme reduction of the distal shelf and cingulid.
Conclusions:
Tartarocyon cazanavei nov. gen. & sp. is a new large amphicyonid from the French locality Sallespisse (12.8–12.0 Ma, France). The specimen may represent a new genus that will be further confirmed or not by future finds. It clearly differs morphologically from the Thaumastocyoninae and Haplocyoninae. It seems that this amphicyonid is a part of the radiation of a group of amphicyonines during the Miocene after MN3 (as exemplified by the genera Pseudocyon, Cynelos, Amphicyon, and Magericyon); it probably derived from a Cynelos-type amphicyonine.
Tartarocyon nov. gen. illustrates the diversity of the amphicyonids in Europe: during MN7/8 amphicyonids were diversified in both the body mass and diet. However, the ecological and diversity reduction of the Amphicyonidae is polyphased. A new comprehensive analysis of the taxonomic and ecologic diversity of the amphicyonids is necessary to better understand the impact of biotic and abiotic factors on the evolution of these predators.
Floréal Solé, Jean-François Lesport, Antoine Heitz and Bastien Mennecart. 2022. A New Gigantic Carnivore (Carnivora, Amphicyonidae) from the late middle Miocene of France. PeerJ. 10:e13457. DOI: 10.7717/peerj.13457
