Ailurus F. G. Cuvier, 1825 . In E. Geoffroy Saint-Hilaire and F. G. Cuvier, Hist. Nat. Mammifèeres, pt. 3, 5(50), "Panda" 3 pp.

TYPE SPECIES: Ailurus fulgens F. G. Cuvier, 1825, by monotypy (Melville and Smith, 1987).

COMMENTS: Biochemical and molecular evidence has suggested that the enigmatic Ailurus is intermediate between the procyonids and the ursids (O'Brien et al., 1985; Sarich, 1973; Tagle et al., 1986; Wayne et al., 1989; Wurster and Benirschke, 1968); more closely related to ursids than to procyonids (Todd and Pressmann, 1968; Zhang and Shi, 1991); or more closely related to the procyonids than to ursids (Goldman et al., 1989). Morphological studies have pointed out the lack of any shared derived features with the procyonids (Bugge, 1978; Decker and Wozencraft, 1991; Ginsburg, 1982; Hunt, 1974; Mayr, 1986; Schmidt-Kittler, 1981; Wozencraft, 1989«, b). Flynn et al. (1988) could not find any unambiguous features to place Ailurus with the procyonids, and only two characters to unite Ailurus with some procyonids, the loss of M/ 3 (shared also with mustelids) and the presence of a cusp on P4 on some, but not all procyonids. Wozencraft (1989«) found 9 shared derived features with the Ursidae, and Decker and Wozencraft (1991) identified 6 unambiguous shared derived features of the procyonids, all of which are lacking in Ailurus . Only phenetic studies have indicated any kind of relationship to the procyonids (Gregory, 1936; Thenius, 1979) and only when compared to Procyon, a derived procyonid (Baskin, 1982, 1989; Decker and Wozencraft, 1991).