According to the original description (Pocock 1895), the gonopod of this species looks absolutely different from the Orthomorpha type, the solenomere showing a couple of denticles near the base, while the solenophore (= lamina lateralis) is produced dorsally before subtending the solenomere. Such a conformation resembles

that of a species of the mainly Papuan tribe Eustrongylosomatini, but the only member of this tribe known to occur west of Borneo is Diglossosternoides curiosus, from the Seychelles (see above). Both Attems (1937) and Jeekel (1968) referred to Orthomorpha oatesii as a species incertae sedis, but Golovatch (1998) included it into his key to Orthomorpha species for the sake of completeness. Revision of Orthomorpha oatesii is required before this species can be properly allocated. The holotype comes from an unspecified locality in southern Tenasserim (= Tanintharyi), Myanmar (Pocock 1895).