Description of a new taxon brookei of Levaillant's Cisticola Cisticola tinniens from the Western Cape, South Africa

Abstract

Herremans, M., Philogene, D., Underhill, G.D., Raijmakers, J.M.H., Underhill, L.G., Johnson, D., Bemitz, H., Bernitz, Z., Bowker, M.B. & De Beer, S.J. 1999. Description of a new taxon brookei of Levaillant's Cisticola Cisticola tinniens from the Western Cape, South Africa. Ostrich 70(3&4): 164- 172. All Levaillant's Cisticolas south of the Limpopo River are currently considered to be of the nominate race. Atlas data indicate a distinct discontinuity in the distribution, separating birds in the winter rainfall region of the Western Cape from those in the summer rainfall zone of South Africa. Western Cape birds breed and moult earlier, are smaller in wing and tail length, but heavier in weight, and lack the distinctive summer plumage of a pale rufous, unstreaked crown in nominate tinniens. Both taxa undergo a partial body moult in spring, but in Western Cape birds this is not a pre- but a peri-breeding moult during which they develop a new nonbreeding plumage. Evidence for early territorial settlement and pairing in juvenile plumage, which is similar to the nonbreeding plumage, was obtained, indicating that the summer plumage may not be a key factor in species recognition. Western Cape birds are described as a new subspecies brookei. A sample of museum specimens contained too many apparently incorrectly sexed birds to reveal sexual bimodality in biometry, and they indicated differences in biometry between taxa in the opposite direction of that found in larger samples of live birds.