New species of antbird (cf Dutch Birding 24: 189, 2002)

Explorations of certain sandy soil habitats in the drainages of the Ríos Tigre and Corrientes in north-eastern Peru have yielded four previously undescribed bird species. Two of these, Ancient Antwren Herpsilochmus gentryi and Mishana Tyrannulet Zimmerius villarejoi have already been named (cf Dutch Birding 20: 142-143, 1998; 24: 71-72, 2002). A third new species, Allpahuayo Antbird Percnostola arenarum, was recently added (Isler, M L, Alvarez Alonso, J, Isler, P R & Whitney, B M 2002. A new species of Percnostola antbird (Passeriformes: Thamnophilidae) from Amazonian Peru, and an analysis of species limits within Percnostola rufifrons. Wilson Bull 113: 164-176). (Please note that although the paper was published in the 'June 2001' issue of Wilson Bulletin, this issue was actually published in February 2002.) The new antbird is probably most closely related to Black-headed Antbird P rufifrons. Seven morphological differences, three vocal and two behavioural characteristics distinguish Allpahuayo Antbird from Black-headed Antbird. As with many other antbirds, the morphological differences are more pronounced in females than in males. Although present data suggest that the Río Napo separates the ranges of Allpahuayo and Black-headed Antbird, this requires substantiation. The authors conclude that Allpahuayo Antbird 'may occupy one of the most specialized habitat niches in the smallest geographic range of any thamnophilid antbird' (although they point out that the recently described Marsh Antbird Stymphalornis acutirostris of south-eastern Brazil may be another candidate for this distinction).
George Sangster