Geographic variation in the Tete veld rat Aethomys ineptus (Rodentia: Muridae) from southern Africa

Abstract

The Tete veld rat Aethomys ineptus Thomas & Wroughton, 1908 is a newly recognized, widely distributed species in southern Africa. Analysis of geographic variation among samples of A. ineptus from southern Africa across a more comprehensive geographical range than has previously been considered suggests that the species has a clinal pattern of variation in which overall cranial size was positively and significantly correlated with longitude. While the suggested clinal pattern of cranial size variation may be valid, the status of some operational taxonomic units, however, may require further refinement involving additional sampling as well as other systematic techniques, such as DNA analysis, cytogenetics and geometric morphometrics. These additional studies may have to include geographic information systems, step-wise multiple regression, and trend-surface analysis involving a wide range of environmental parameters to identify factors that may explain the nature and extent of the delineated pattern of geographic variation within A. ineptus from southern Africa. Consequently, the seven previously recognized subspecies recently assigned to A. ineptus in southern Africa (A. chrysophilus tzaneenensis Jameson, 1909; A. c. pretoriae Roberts, 1913; A. c. magalakuini Roberts, 1926; A. c. capricornis Roberts, 1926; A. c. tongensis Roberts, 1931; A. c. fouriei Roberts, 1946; and A. c. harei Roberts, 1946) are only provisionally synonymized.