Eucyon adoxus ( Martin, 1973 )

Rook, Lorenzo, 2009, The wide ranging genus Eucyon Tedford & Qiu, 1996 (Mammalia, Carnivora, Canidae, Canini) in the Mio-Pliocene of the Old World, Geodiversitas 31 (4), pp. 723-741 : 732

Eucyon adoxus ( Martin, 1973)

TYPE LOCALITY. — St-Estève, near Perpignan ( France).

AGE. — Early Pliocene (Ruscinian; MN 15).

GEOGRAPHIC RANGE. — France, Spain.

This is a relatively large Pliocene dog from MN15 of St-Estève, near Perpignan, in southern France ( Fig.2 ). Eucyon adoxus is characterized by an elongate rostrum and mandible and is clearly not a vulpine (as is claimed by some authors, e.g., Pons Moyá & Crusafont Pairó 1978), because it does not have the typical vulpine depression in the region of postorbital constriction of the frontal bones ( Rook 1992, 1993). Although the mandibles of the Perpignan dog show features typical of Eucyon, Tedford & Qiu (1996) note that some of the derived features they display (mainly in the dentition) are synapomorphies for other canine lineages and therefore they could represent a taxon different from Eucyon . As discussed in Rook (1993) and then supported by Wang &Tedford (2008), it is maintained here the opinion that the Perpignan dog is one of the latest representatives of the evolutionary differentiation of the genus Eucyon in Europe ( Fig. 2 ). A number of contemporary findings occur in Europe (La Calera I, Spain: Alcalá Martínez 1994; Red Crag, UK: Lydekker 1885; Rook 1992, 1993).

The record of this species includes a magnificently preserved type skull and mandibles (specimen RSS45; Fig.3A, B ).The material is good enough for allowing a reconstruction of the life appearance of the head of this species( Fig.3D ),herein joined with the reconstruction of principal jaw-abductor muscles ( Fig. 3C ).

Figures

FIG. 2. — The early and mid-Pliocene Eucyon Tedford & Qiu, 1996 distribution: A, during early and mid-Pliocene times (◇) the genus Eucyon had a wide distribution across Eurasia. The very late record of the genus (○, late Pliocene/middle Villafranchian) seems to be limited to central Asia and to the more arid areas of eastern Eurasia (Turkey, North Africa); B, the typical Pliocene species from Europe E. adoxus (Martin, 1973) from St-Estève (near Perpignan, France; MN 15), cast of skull (approximate length 18 cm) and mandible (reversed) RSS-45 (Basel Naturhistorisches Museum);C, E. davisi (Merriam, 1911) from Hsia Kou (Yushe basin, China; Pliocene),cast of skull (approximate length 15 cm) F:AM-97056 (American Museum of Natural History, New York); D, E. zhoui Tedford & Qiu, 1996 from Chao Chuang (Yushe basin, China; Pliocene), cast of skull (reversed) and mandibular ramus (approximate length of mandibular ramus 10 cm) F:AM-97048 (American Museum of Natural History, New York).

FIG. 3. — Eucyon adoxus (Martin, 1973) from St-Estève (near Perpignan, France; MN 15): A, type specimen RSS 45, approximate length of the skull 18 cm;B, skull and mandible reconstruction based on type specimen RSS 45; C, reconstruction of principal jaw- abductor muscles positioned on the reconstructed skull; D, life appearance of the head.