Species Limits in Antbirds: The Thamnophilus Punctatus Complex Continued

In a previous study (Isler et al. 1997) we examined species limits in the Thamnophilus punctatus complex of the Neotropics. We recommended that six taxa be considered species, but were unable to make recommendations regarding two morphologically distinct and geographically restricted taxa, leucogaster and huallagae, due to the lack of vocal recordings which were essential to our methodology. Analysis of newly obtained recordings has found that vocal differences support the separation at the species level of leucogaster and huallagae from five of the six species in the complex (T. atrinucha, T. stictocephalus, T. sticturus, T. pelzelni, and T. ambiguus). However, leucogaster and huallagae could not be distinguished vocally from each other nor from nominate punctatus to an extent that supported species status, and they are retained as subspecies under our recommended guidelines (Isler et al. 1998, 1999). The Thamnophilus punctatus complex affords an interesting opportunity for future molecular studies that compare the genetic distances among populations that have differentiated vocally and those that have not. The question of species status of leucogaster and huallagae is pressing because the ranges of both taxa are limited to sub-Andean basins in northwestern Peru and southwestern Ecuador that increasingly are under cultivation.