Xanthotropis, a new genus in the Neotropical millipede subfamily Aphelidesminae (Diplopoda, Polydesmida, Aphelidesmidae).

The monotypic taxon Xanthotropis n. gen. is established to accommodate Haematotropis media Golovatch, Hoffman Spelda, 2004, known only from the vicinity of Manaus, Brazil, as it is incompatible with both its originally assigned genus and Aphelidesmus Brölemann, 1898, a suggested alternative. Xanthotropis is defined primarily by minute teeth on paranota 2-4, a sublinear posterior margin of the telson, and an elongated, distally expanded/laminate acropodite. The Aphelidesmidae Brölemann, 1916, range from northeastern Mexico and Tobago to northern Brazil and southwestern Peru; a questionable more-northerly record, from Monterey, Mexico, requires verification with fresh material. One of two families of the polydesmidan superfamily Platyrhacoidea (Leptodesmidea), Aphelidesmidae comprises two subfamilies, the nominate and Amplininae Hoffman, 1954. The latter has been addressed by several authors, and we here review Aphelidesminae by providing full synonymies, a literature review, and a key to its four genera: Aphelidesmus Brölemann, 1898; Haematotropis and Ochrotropis, both by Jeekel, 2000; and Xanthotropis n. gen.