Beamys cf. hindei Thomas, 1909

Denys, Christiane, Lalis, Aude, Lecompte, Émilie, Cornette, Raphaël, Moulin, Sibyle, Makundi, Rhodes H., Machang, Robert S., Volobouev, Vitaly & Aniskine, Vladimir M., 2011, A faunal survey in Kingu Pira (south Tanzania), with new karyotypes of several small mammals and the description of a new Murid species (Mammalia, Rodentia), Zoosystema 33 (1), pp. 5-47 : 34-36

Beamys cf. hindei Thomas, 1909

Beamys hindei Thomas, 1909: 61 .

Three relatively young individuals (one male and two females) of the lesser pouched rat were collected exclusively in the Kichi Forest. Their general size fits within the lower range of the species value provided by Kingdon (1974). By studying the distribution and morphology of B. hindei from new localities of Kenya and Tanzania, Fitzgibbon et al. (1995) concluded that there is a size cline among the populations from north to south. Because of the taxonomic confusion about which species is present in coastal area of Tanzania, we have compared our specimen with the two Beamys species holotypes and the populations of Kenya, south Tanzania and Malawi. As suggested by its name, B. major is larger compared to Tanzanian B. hindei specimens, despite some overlap in the HB and TL proportions ( Table 15). We confirmed that B. hindei HF is

15 17

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smaller than that of B. major , but the KP specimens fit well between the two groups. When comparing the skulls and molars proportions ( Table 16) it is clear that the Selous Kingu Pira Beamys share with B. hindei the smaller molars and slightly smaller general size of the skull.

Fitzgibbon et al. (1995) have made standard karyotypes of four specimens of Arabuko, Sokoke Forest, Kilifi district, Kenya (BMNH 1993.18 to 25, cf. Table 15) and found a diploid chromosome number of 2n = 52 with no more precision. The karyotype of Kingu Pira Beamys cf. hindei displays a c hromosomal set consisting of 54 autosomes and two gonosomes (2n =56, FNa= 72) ( Fig.19 ). Both sex chromosomes, metacentric X and submetacentric Y, are the largest in the set and thus may probably represent distinctive karyotypic feature of this species. Because the type specimen of B. hindei comes from Taveta in SE Kenya (at the Tanzanian border), we may confirm that the Kenya specimens of B. hindei may represent a different species than the southern Tanzanian ones. Such a chromosomal differentiation may result from the fragmented distribution of the species.

Subfamily GERBILLINAE Gray, 1825

Figures

FIG. 19. — Standard karyotype of Beamys cf. hindei Thomas, 1909 specimen from Kichi forest (MNHN-CG2007-1232).