Chromosome banding analysis (G‐ and C‐ bands) of two species of Lemniscomys from Tanzania, Lemniscomyszebra and Lemniscomysrosalia, and of a third species from Benin, Lemniscomysstriatus was carried out to trace the pattern of chromosomal evolution of the genus. The G‐banding pattern comparison makes it possible to identify chromosomal rearrangements between the karyotypes. The two Tanzanian species (L. rosalia 2n=54, FNa=62; and L. zebra 2n=54, FNa=58) differ due to two pericentric inversions. A X polymorphism was detected in both species. Furthermore, L. rosalia shows two forms of the Y chromosome. The banding pattern of L. striatus (2n=44; FNa=68) from Benin allows identification of five Robertsonian fusions with respect to L. zebra. Moreover L. rosalia is characterized by a karyotype which is different from the one described for South Africa (2n=48; FNa=62), and therefore it should be considered as a different species. Comparative banding analysis with another Arvicanthine species (Arvicanthis dembeensis, 2n=62, FNa=62) showed complete homology in G‐bands between the two genera, the differences involving tandem fusions, pericentric inversions, and Robertsonian fusions.

The Ethiopian Myomys -Stenocephalemys complex has long constituted a taxonomic and systematic puzzle. The species occur at different altitudes, from 1000 up to 4300 m a.s.l., and show remarkable adaptations to high altitude habitats. The four species forming the complex, M. albipes, M. ruppi, S. albocaudata and S. griseicauda, are all endemic to the country and constitute a monophyletic group. We describe their karyotypes, including their G-and C-banding patterns, and their allozyme patterns. Phylogenetic trees based on chromosomal rearrangements and allozymes support the current taxonomy. Nonetheless, comparisons with genetic similarity data and other hypotheses drawn from mtDNA and geometric morphometrics show substantial disagreement, and therefore it is not possible to claim the paraphyly of Stenocephalemys which would then include Myomys.

Karyotypes of two endemic species of hare from Ethiopia, Lepus habessinicus and L. starcki were studied and compared to that of L. europaeus. L. starcki has a fragmented range in the high Ethiopian plateaus and is considered a relict form of L. europaeus. In contrast, L. habessinicus occurs at lower altitudes, and is an arid-country species. The species share a 2n = 48 and a FNa = 88 common to all representatives of the genus. No sign of karyotypic differentiation is evident from G-banding and Ag-NOR location. These data support the hypothesis of pronounced karyotypic conservativism in the genus Lepus.Resume. -On a etudie le caryotype de deux especes de lievres endemiques d'Ethiopie, Lepus habessinicus et Lepus starcki et on les a compares ä celui de Lepus europaeus. L. starcki est distribue irregulierement sur le plateau ethiopien et est considere comme une forme relicte de L. europaeus, tandis que L. habessinicus vit ä des altitudes plus basses et est considere comme une espece xerophile. Les especes ethiopiennes partagent le meme caryotype ä 48 chromosomes (NFa = 88), commun a l'ensemble du genre Lepus. L'analyse des bandes G et Ag-NOR n'a mis en evidence aucune difference caryotypique entre les 3 especes. Ces donnoes confirment 1'hypothese que, chez les lievres, le caryotype est fortement conserve.

The African rats of the genus Arvicanthis have been widely studied during recent years to clarify species boundaries and phylogenetic relationships. The wide chromosomal variability of the genus has been highlighted in several studies, with each accepted species characterised by its individual karyotypes and others being revealed as cryptic species. In the present paper we report the karyotype and the C- and G-banding patterns of the two species A. nairobae and A. neumanni from seven localities of Tanzania, an area of the range poorly studied. The two karyotypes were compared to that of A. niloticus, which is considered to be primitive. The karyotype of A. neumanni is characterised by 2n = 53-54 and NFa = 62. This karyotypic variability depends on a widespread Robertsonian polymorphism. The karyotype of A. nairobae shows 2n = 62 and NFa = 78; it diverges from that of A. niloticus through one reciprocal translocation, five inversions and three heterochromatic additions. The comparison with the karyotypes of other species of the genus showed that A. neumanni belongs to the east African lineage (with A. abyssinicus, A. blicki, A. niloticus), while A. nairobae is closer to the central and the west African representatives which were all previously under the name of A. niloticus (ANI-2, ANI-3, ANI-4). The distribution of A. nairobae in east Africa opens new scenarios in the biogeographical pattern of evolution of the genus.

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