Otomys F. Cuvier 1824

Otomys F. Cuvier 1824, Dentes des Mammiferes: 255.

Type Species: Euryotis irrorata Brants 1827

Synonyms: Anchotomys Thomas 1918; Euryotis Brants 1827; Lamotomys Thomas 1918; Oreinomys Trouessart 1880; Oreomys Heuglin 1877; Palaeotomys Broom 1937; Prototomys Broom 1948 .

Species and subspecies: 19 species:

Species Otomys anchietae Bocage 1882

Species Otomys angoniensis Wroughton 1906

Species Otomys barbouri Lawrence and Loveridge 1953

Species Otomys burtoni Thomas 1918

Species Otomys cuanzensis Hill and Carter 1937

Species Otomys dartmouthi Thomas 1906

Species Otomys denti Thomas 1906

Species Otomys dollmani Heller 1912

Species Otomys irroratus Brants 1827

Species Otomys jacksoni Thomas 1891

Species Otomys lacustris G. M. Allen and Loveridge 1933

Species Otomys laminatus Thomas and Schwann 1905

Species Otomys maximus Roberts 1924

Species Otomys occidentalis Dieterlen and Van der Straeten 1992

Species Otomys orestes Thomas 1900

Species Otomys saundersiae Roberts 1929

Species Otomys tropicalis Thomas 1902

Species Otomys typus Heuglin 1877

Species Otomys uzungwensis Lawrence and Loveridge 1953

Discussion: Whereas Bohmann (1952) included all otomyine species in Otomys, most systematists have accorded the large-bullar forms separate generic status as Parotomys (see below), and we follow Thomas (1918 b) in recognizing Myotomys as genus (see subfamily remarks). Roberts (1951) also treated Lamotomys as generically distinct, but cladistic interpretation of allozymic and immunologcial data, albeit limited to few species so far, clearly affiliate its type species laminatus with other Otomys (Contrafatto et al., 1994; Taylor et al., 1989). Oldest known fossil Otomys species date from the middle to late Pliocene (2-3.5 million years ago) in South Africa and from early Pleistocene (1-2 million years ago) in East Africa (see Denys, 1989 a; Sénégas, 2001; Sénégas and Avery, 1998). Synonymy of the fossil Prototomys follows the observations of Avery (1998), who noted the marginal distinction of its type species, P. campbelli, from living O. saundersiae .

The species richness and biogeographic diversification within Otomys were grossly obscured by forcing its exceptional morphological variation into the polytypic application of the biological species concept that prevailed over the middle 1900s (e.g., Bohmann, 1952; Dieterlen, 1968; Ellerman et al., 1953; Misonne, 1974; Petter, 1982). Deconstructing these polyphyletic accretions into diagnosable, genetically homogeneous species is much progressed in southern Africa (see Taylor and Kumirai, 2001, for overview) and selectively in other areas (e.g., Dieterlen and Van der Straeten, 1992). As we noted in 1993, the occurrence of greater specific endemism throughout the isolated East African highlands and volcanoes deserves more serious consideration than it has received to date. Persuant to such revisionary attention, the early syntheses of Wroughton (1906), Dollman (1915), and Hollister (1919) offer a sounder foundation from which to address questions of specific status and distribution in the East African region. Such investigations should emphasize comparisons both among mountain ranges and along their slopes, drawing upon topotypic examples to explicitly address taxonomic and biogeographic problems at issue. In particular, the possibility of multiple independent originations (speciation) of otomyines in afro-alpine environments on East African mountain tops should be the working hypothesis to be disproven.