Uranomys ruddi Dollman, 1909

Denys, Christiane, Missoup, Alain Didier, Nicolas, Violaine, Sylla, Morlaye, Douno, Mory, Kadjo, Blaise, Lalis, Aude & Monadjem, Ara, 2025, Annotated checklist of rodents from a biodiversity hotspot, Mount Nimba (West Africa), Zoosystema 47 (27), pp. 617-689 : 649

Uranomys ruddi Dollman, 1909

Uranomys ruddi Dollman 1909: 552 .

REMARKS

The type specimen came from Mount Elgon ( Uganda) but no significant morphological differences were detected to support the presence of a higher diversity in the genus despite some chromosomal variability. The species was reported by Heim de Balsac & Lamotte (1958) on the Guinean side of Mount Nimba with two individuals from Ziela and seven specimens from Gouécké. In 1961 Pierre Aguesse collected an additional individual. Since that time no new specimens have been collected by Gautun et al. (1986), Misonne & Verschuren (1976), or Coe (1975). We were unable to trap new specimens during our fieldworks.

The Nimba specimens display a grey-brown dense and short dorsal pelage and grey-white belly, not spiny, with a naked short tail. The specimen MNHN-ZM-1981-1123 fits the size range of the Côte d’Ivoire specimens ( Table 7 ). On the ventral part of the skull the palate bone extends above the mesopterygoid fossa as in Acomys I. Geoffroy, 1838 . Proodont incisors, a large interorbital constriction, a rounded braincase, and a short nasal rostrum are typical of the species morphology. On ventral view the incisive foramina extend in the palate between the t1 cusps of M1. The dental rows are parallel and the tympanic bullae are oblique, oval and small. Skull measurements are provided in Table 8 and the Mount Nimba Uranomys fit well within the variability of other Guinean and Côte d’Ivoire representatives. As in other Deomyinae the U. ruddi molars are constituted by rows of cusps similar to the murinae pattern, with a t1 and a t4 on the upper M1. This subfamily differs from the Murinae by the cusp disposition on the upper M3 with the absence of t1 and presence of t3 and by the very oblique pattern of cusps on this tooth. In one specimen (MNHN-ZM-1981-1123), the whole labial row of cups (t3, t6, t9) is not well distinguished and not separated by a deep valley from the central row of cusps. On the lower molars, cingular cusps are abundant on both lingual and labial sides of m1.