Range Description

T. napu, as constituted here (that is, excluding T. versicolor of Indochina and T. nigricans of the Philippines) occurs in the Sundaic subregion, extending some way up the Thai–Malay peninsula, in the following countries: Brunei, Indonesia (Kalimantan, Sumatra, and many small islands), Malaysia (West Malaysia, Sabah, Sarawak, and many small islands), Myanmar (far south only), and Thailand (south only) (Meijaard and Groves 2004). Grubb (2005) listed Singapore, following Chasen (1940), and although it was not explicitly recorded from this island either by Meijaard (2003; review of mammals on Southast Asian islands) or by Meijaard and Groves (2004; review of Tragulus distribution), the Raffles Museum of Biodiversity Research, Singapore, holds specimens collected in the 1920s. There are no subsequent records and it is believed to be extinct (K. Lim pers. comm. 2008). Grubb (2005) also included Cambodia, Lao PDR, and ‘Indochina’ in the range of T. napu; but this was founded on the assumption that because T. versicolor, formerly considered a subspecies of T. napu, occurred in Viet Nam, T. napu must presumably occur in intervening Lao PDR and Cambodia. There is, for example, a map of such a conterminous range for T. napu in Corbet and Hill (1992). There is no evidence of such a distribution and, given the distribution patterns of other species, absolutely no reason to expect that it would have such a range, even if T. napu and T. versicolor are closely allied. Recent surveys in both countries have not suspected the species (Duckworth et al. 1999; R.J. Timmins pers. comm. 2008).

The northern limit on the Thai–Malay peninsula is not well clarified. Despite fairly intensive camera-trapping in Kuiburi National Park, Thailand (12°N and thus within the generally-assumed range for T. napu), Greater Chevrotain has not been photographed there. It must be scarce in this park if it occurs at all (Steinmetz et al. 2007; R. Steinmetz pers. comm. 2008).

Caution is needed in interpreting modern records of T. napu from anywhere outside the specimen-validated range (as presented in Meijaard and Groves 2004); some camera-trap studies seem to have taken an essentially arbitrary attitude on naming their photographs of chevrotains, resulting in published listings of T. napu from, for example, northern Thailand. Because such listings never highlight the significance of such records, let alone discuss them, all are assumed to be in error, and are not discussed further, here.