Crawford Cabral (1989, 1996) considered nigratus conspecific with the earlier described flavescens Bocage, 1889 from Angola. This classification has been followed by others and is adopted here. While the 'Black Mongoose' (Myonax nigratus Thomas, 1928) was initially described as a species in its own right, there has been much controversy surrounding its species status (summarised in Rapson 2011), and notably it was regarded as a subspecies of the Cape Grey Mongoose (H. pulverulentus) by Ellerman et al. (1953). However, unique characteristics of nigratus distinguishing it from both H. pulverulentus and Common Slender Mongoose (H. sanguineus) include craniometric variables - size of anterior and posterior chambers of the auditory bulla, presence or absence of the postorbital bar and the number of lower premolars - and pelage colour (Watson and Dippenaar 1987, Watson 1990, Taylor and Goldman 1993). Rapson et al. (2012) presented the first genetic evidence indicating that it is indeed a species separate from both H. pulverulentus and H. sanguineus. In addition, nigratus may actually constitute a species distinct from H. flavescens, as highlighted by Rathbun and Cowley (2008) who noted the remarkable difference in pelage colouration between specimens from Angola and Namibia, the lack of comparative data between the two forms in Crawford-Cabral's papers, and the possible ecological differences between the two forms. Comparative ecological, morphometric and genetic studies of individuals from Namibia and Angola are needed to resolve this taxonomic conundrum. The Kaokoveld Slender Mongoose, alongside other 'small' African Herpestes species, are here retained in the genus Herpestes, although Watson and Dippenaar (1987) included them in the genus Galerella, a classification which is backed up by molecular studies.