Peters's Mouse

discussion

REMARKS The karyotypes of two specimens displayed the standard karyotype for this species (2 N = 36, NFa = 34), the Cyt B sequencing allowed to attribute these specimens to M. setulosus. This karyotype is similar to the one of a M. setulosus from Sangassou (forest Guinea) (Kan Kouassi et al. 2008). The tail length is shorter than HB length. The dorsal pelage is grey light brown and the belly white. There is a line of yellow-light brown hairs at the demarcation between the dorsal and ventral parts. The tail is short and unicolored. This species is characterized by being larger than M. baoulei and M. minutoides (Tables 7; 8). The skull displays a short and wide rostrum, a large CIO and a rounded braincase. In ventral view, the incisive foramina are large and enter into the palate before the first lobe of the M 1 /. The tympanic bullae are small and oval. Mus setulosus skulls display similar sizes on both sides of Mount Nimba. Their respective values of skull distances fit well with previous work for Guinean and Ivorian specimens molecularly typed by Kan Kouassi et al. (2008). Mus setulosus has a longer toothrow compared to M. baoulei and M. minutoides and the m 3 has two lobes as opp

Annotated checklist of rodents from a biodiversity hotspot, Mount Nimba (West Africa)

discussion

Discussion: Subgenus Nannomys. A distinct species sometimes confused with M. minutoides, which occurs over approximately the same region (Rosevear, 1969). Multivariate analysis of morphometric traits by Macholán (2001) indicated that M. setulosus and M. minutoides were distantly related. Both pasha (Thomas, 1910 a) and proconodon (Rhoads, 1896) were originally described as species; Osgood (1936) associated pasha with M. proconodon, and we agree with his identification. F. Petter and Matthey (1975) regarded pasha as a species, noting that it might be referrable to M. setulosus. Both Osgood (1936) and Yalden et al. (1976) recognized proconodon as a species endemic to Ethiopia. Our study of Osgood's specimens, some of which are near-topotypes, revealed that their morphological traits fell within the range of variation typical of M. setulosus. Our identification was foreshadowed by F. Petter and Matthey (1975), who cited the range of M. setulosus to include Ethiopia, based on a letter from J. Prevost. Chromosomal data for samples from West Africa documented by Jotterand (1972), Jotterand-Bellomo (1981, 1986), and Matthey (1964).

Order Rodentia - Family Muridae

distribution

Distribution: From Senegal (Duplantier and Granjon, 1992), Guinea (Mt Nimba) and Sierra Leone; eastward through Liberia, Côte d’Ivoire, Ghana, Togo, Benin, Nigeria, Cameroon, Gabon, Central African Republic, N Dem. Rep. Congo (Orientale), S Sudan, WC and S Ethiopia; to N Uganda and W Kenya (range documented by Grubb et al., 1998; Rosevear, 1969; F. Petter and Genest, 1970; our study of samples in AMNH, BMNH, FMNH, and USNM).

Order Rodentia - Family Muridae

discussion

COMMENTS: Subgenus Nannomys. A distinct species sometimes confused with M. musculoides, which occurs over approximately the same region (Rosevear, 1969). Both pasha (Thomas, 1910 a) and proconodon (Rhoads, 1896) were originally described as species. Osgood (1936) associated pasha with M. proconodon, and we agree with his identification. Petter and Matthey (1975) regarded pasha as a species, noting that it might be referable to M. setulosus. Both Osgood (1936) and Yalden et al. (1976) recognized proconodon as a distinct species endemic to Ethiopia. Our study of Osgood's specimens, some of which are near-topotypes, revealed that their morphological traits fell within the range of variation typical of M. selulosus. Our identification was forshadowed by Petter and Matthey (1975) who cited the range of M. selulosus to include Ethiopia, based on a letter from J. Prevost. Chromosomal data for samples from W Africa were documented by Jotterand (1972), Jotterand-Bellomo (1981, 1986), and Matthey (1964).

Order Rodentia - Family Muridae