West African Praomys

discussion

REMARKS Described from Mount Coffee in Liberia, it was neither recorded by Heim de Balsac & Lamotte (1958) nor by Gautun et al. (1986) from the Guinean side of Mount Nimba, perhaps due to a lack of taxonomic knowledge at that time when P. rostratus was typically confounded with P. tullbergi. The Nimba P. rostratus are characterized by a dorsal reddish-brown pelage and a white belly with a grey basis. The tail is longer than HB (mean Tail: HB ratio: 112 %, range: 105 - 128). The main difference between P. rostratus and P. tullbergi is size, with P. rostratus being larger and heavier on average than P. tullbergi. Praomys rostratus has a longer hindfoot (mean: 24.5 mm) but there is some overlap between individuals of both species as presented in Table 7. Like other representatives of the tullbergi complex, the specimens of the Nimba P. rostratus do not harbour any marked fronto-parietal crests. The rostrum is long, the brain case wide and round. The infraorbital foramen stops just at the level of the t 4 of the M 1. The tympanic bullae are small and round. On the upper molars, the t 2 and t 3 cusps are not completely aligned transversally, the t 1 is not isolated. There is the presenc

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

discussion

Discussion: 2 n = 34 (Gautun et al., 1986). Member of the P. tullbergi complex. Originally described as a subspecies of tullbergi, but Van der Straeten and Verheyen (1981) distinguished rostratus from tullbergi by its greater body size, noted that both kinds were sympatric, and raised rostratus to specific rank. A similar distribution of body sizes, as well as different ecologies, were claimed by Gautun et al. (1986) from Mt Nimba, and they also separated their samples into either P. tullbergi or P. rostratus. However, the existence of a larger-bodied species in W Africa related to P. tullbergi requires verification because published data separating the two is not convincing according to L. Granjon (in litt., 2002): " The text by Gautun et al. (1986) is not clear, and in Mali we now have a good sample of 2 n = 34 (all acrocentric autosomes) Praomys from various localities with measurements covering the entire range of the two species as analyzed by Van der Straeten and Verheyen (1981), in which no individual measurement would distinguish between the two species. " If proved a distinct species, P. rostratus would be part of the murine fauna endemic to W Africa (see account of Grammo

Order Rodentia - Family Muridae

distribution

Distribution: Recorded only from forest in Liberia, C Guinea (Ziegler et al., 2002), Mt Nimba region of Guinea, and Côte d’Ivoire; limits unresolved.

Order Rodentia - Family Muridae

discussion

COMMENTS: Originally described as a subspecies of tullbergi, but Van der Straeten and Verheyen (1981) distinguished rostratus from tullbergi by its greater body size, noted that both kinds were sympatric, and raised rostratus to specific rank. A similar distribution of body sizes, as well as different ecologies, were recorded by Gautun et al. (1986) from Mt Nimba, and they also separated their samples into either P. tullbergi or P. rostratus. P. rostratus is part of the murine fauna endemic to W Africa (see account of Grammomys buntingi).

Order Rodentia - Family Muridae