Skin, skull and skeleton characters of mouse deer (Mammalia, Tragulidae), with keys to the species

At present, four species are recognized within the family Tragulidae: viz. Hyemoschus aquaticus (Ogilby, 1841), living in tropical West Africa and Central Africa, north of the Congo River; Tragulus meminna (Erxleben, 1777), occurring on Sri Lanka (Ceylon) and in the south of peninsular India; and the largely sympatric species Tragulus javanicus (Osbeck, 1765) and Tragulus napu (F. Cuvier, 1822), both found in southeast Asia and on the Sunda islands west of the Strait of Makassar. Keys to these four species are presented. Diagnostic non-meristic characters in the skeleton are found for H.aquaticus and T.meminna, but not for T.javanicus and T.napu. The latter two species can be identified on meristic characters in the appendicular skeleton: T.napu has stronger and broader feet than T.javanicus. The taxonomy of the family Tragulidae is outlined in table I.