Cuon Hodgson, 1837

TEDFORD R. H., WANG X. & TAYLOR B. E., 2009, Phylogenetic Systematics Of The North American Fossil Caninae (Carnivora: Canidae), Bulletin of the American Museum of Natural History 2009 (325), pp. 1-218 : 157

Cuon Hodgson, 1837

Chrysaeus Smith, 1839: 167 .

Primoevus Hodgson, 1842: 39 .

Primaevus Gray, 1843.

Cuon Agassiz, 1846: 113 .

Cynotherium Studiati, 1857: 657 .

Anurocyon Heude, 1888: 102 .

Crassicuon Kretzoi, 1941: 118 .

Semicuon Kretzoi, 1941: 119 .

Type Species: Cuon primaevus Hodgson, 1837 .

Distribution in North America: Cuon alpinus Rancholabrean (latest Pleistocene), northeastern Mexico.

Diagnosis: The osteological differentiation of species of Cuon from those of Xenocyon , and the morphologically related Lycaon pictus , lies principally in the extreme hypercarnivory of Cuon spp. : loss of m3; reduction of m2 to single or poorly differentiated double-rooted condition with further simplification of crown involving great reduction and loss of metaconid so that it resembles m3 of other canines; loss of m1 entoconid and any remnant of the cristid connecting it with hypoconid, and further reduction of metaconid to very small size and loss (usually as individual variation in Cuon populations); anterior premolars also with prominent, highcrowned principal cusps, p2 and p3 usually with posterior cusp; large p4 whose principal cusp is as high or higher than m1 paraconid, and presence of shelflike anterior cingulum that may be produced into anterior cusp; M1 lacking hypocone, although there may be remnant of posterolingual cingulum; M2 very reduced, but retaining tribosphenic form.

Discussion: The living kinds of Cuon are variously interpreted as races or full specific taxa: C. primaevus (Hodgson, 1837) , from the Himalayas and Tibetan Plateau; C. alpinus (Pallas, 1811) , from northern Asia (Urals to Altai); C. dukunensis (Sykes, 1831) , the dhole of peninsular India and the Deccan Plateau; and C. javanicus (Desmarest, 1820) , from southeastern Asia and the larger islands of Indonesia west of Wallace’s Line. Pocock (1936) advocated union under C. javanicus , but most authorities now use the specific name C. alpinus for all living Cuon . In the fossil record Cuon appears in the medial Pleistocene of Europe as C. alpinus priscus (Thenius), 1954 , and in southeastern Asia as C. javanicus antiquus ( Matthew and Granger, 1923) . Late Pleistocene northern Eurasian forms are usually placed in C. alpinus fossilis ( Nehring, 1890) or, in the latest Pleistocene, C. alpinus europaeus (Bourguignat, 1868) . In the course of describing the material of Cuon alpinus fossilis from late Pleistocene deposits at Heppenloch, Germany, Adam (1959) viewed the record of C. alpinus in Europe as a clade (Formenkreis) beginning with C. a. priscus , passing through C. a. fossilis to C. a. europacus, with progressive modifications of the molar dentition, especially m2 to a unirooted condition and loss of metaconid; the p4 increases in crown height and prominence of the anterior cusp. The North American examples described below belong to the terminal part of this clade.