. Bulletin of the British Ornithologists' Club. Birds. 145. 1988 108(3) HlO'S Hl5°S —|20°S H25*S H30*S H35*S Figure 1. The distribution of the Palewinged Starling Onychognathus nabouroup, based both on museum specimens and other records. Dots indicate localities plotted on the quarter- degree square system; the dashed line separates northern and southern birds as described in the text. Points of reference along the coast are the Cunene River (CR), Walvis Bay (WB), the Orange River (OR), Cape Town (CT) and Port Elizabeth (PE). variation in this species is "reputed
. Bulletin of the British Ornithologists' Club. Birds. 145. 1988 108(3) HlO'S Hl5°S —|20°S H25*S H30*S H35*S Figure 1. The distribution of the Palewinged Starling Onychognathus nabouroup, based both on museum specimens and other records. Dots indicate localities plotted on the quarter- degree square system; the dashed line separates northern and southern birds as described in the text. Points of reference along the coast are the Cunene River (CR), Walvis Bay (WB), the Orange River (OR), Cape Town (CT) and Port Elizabeth (PE). variation in this species is "reputedly clinal", and does not delimit their ranges on his map of the distribution of the 2 Onychognathus species in southern Africa. However, in the text Clancey (p. 254) gives the range of benguellensis as the Kaokoveld, northwestern Namibia, and southern and coastal Angola. Specimens from Angola are few, so I initially divided the material into 2 groups: birds south of 21 °S, and birds north of this line (Fig. 1). Their measurements are compared in Table 1. While the mean measurements for southern birds are larger than those for northern birds, there is con- siderable variation within each group, and an analysis of variance showed that only the wing lengths of female birds differed significantly between the 2 populations. Wing-length is significantly correlated with latitude in both sexes, but tail- and tarsus-length are not (Table 2). The pattern of size variation in this species is not an obvious cline as defined in Campbell & Lack (1985). Colour of the remiges is a poor differentiating character. Sharpe (1904) remarked that the type specimen of benguellensis was indistinguishable from Damaraland birds, and Hoesch & Niethammer (1940) concluded that their specimens from Damaraland, Namibia belonged to the nomi- nate race, since none had pure white remiges as described by Neumann. Please note that these images are extracted from scanned page images that may have
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