Castiglia Riccardo, Corti Marco, Colangelo Paolo, Annesi Flavia, Capanna Ernesto, Verheyen Walter, Sichilima Alfred Matafwali, Makundi Rhodes
Dipartimento di Biologia Animale e dell'Uomo, Università di Roma La Sapienza, Roma, Italy.
Hereditas. 2003;139(2):81-9. doi: 10.1111/j.1601-5223.2003.01763.x.
Aethomys is a common and widespread rodent genus in the African savannas and grasslands. However, its systematics and taxonomy are still unclear as no study has covered the entire range. In fact it might not be a monophyletic genus and perhaps should be split into two subgenera, Micaelamys and Aethomys. In this paper, we present findings based on the cytogenetics and the entire cytochrome b sequence of two species from Zambia (A. kaiseri) and Tanzania (A. chrysophilus), and we compare them with the sequences of a South African species (A. namaquensis) and other allied muroid genera. Comparison of the banded chromosomes revealed complete G-band homology between the autosomes of the two species. However, the X and Y chromosomes clearly differ in size and in C- and G-banding, being much larger in A. kaiseri. Comparison of the cytochrome b sequences places the separation between A. kaiseri and A. chrysophilus at 4.49 Mya, a period of intense speciation in other African muroids. The resulting phylogeny strongly supports the idea of a paraphyletic group, suggesting the need to elevate the previously described subgenera to the genus rank.
埃氏鼠属是非洲稀树草原和草原上常见且分布广泛的啮齿动物属。然而，由于尚无研究涵盖其整个分布范围，其系统学和分类学仍不明确。事实上，它可能不是一个单系属，或许应分为两个亚属，即米氏鼠亚属和埃氏鼠亚属。在本文中，我们展示了基于赞比亚的一个物种（凯氏埃氏鼠）和坦桑尼亚的一个物种（金色埃氏鼠）的细胞遗传学和完整细胞色素b序列的研究结果，并将它们与一个南非物种（纳马夸埃氏鼠）及其他相关鼠科属的序列进行比较。带型染色体的比较显示这两个物种的常染色体之间存在完全的G带同源性。然而，X和Y染色体在大小以及C带和G带上明显不同，在凯氏埃氏鼠中要大得多。细胞色素b序列的比较表明，凯氏埃氏鼠和金色埃氏鼠的分化发生在449万年前，这是其他非洲鼠科动物物种形成的活跃时期。由此产生的系统发育强烈支持并系群的观点，这表明有必要将先前描述的亚属提升为属级。
