Mate recognition systems and species limits in a warbling-finch complex (Poospiza nigrorufa/whitii)

ABSTRACTSpecies limits in the Poospiza nigrorufa/whitii complex are not well understood. Three taxa formally described as species are now considered as subspecies (nigrorufa, whitii and wagneri) of a widespread species. The heavier nigrorufa has longer bill, tarsus and wings, is slightly dimorphic with males showing tawny rufous throat, breast and flanks, and brownish grey upper parts with a slate tinge, while females differ in the orange tinge of ventral parts and in the more olivaceous upper parts; inhabits shrubby open areas and wetlands with reeds and bulrushes in eastern southern South America, and gives a simple three-note pattern that repeats to form the song and diagnostic calls. The lighter whitii (including wagneri as a synonym) has a shorter bill, tarsus and wings, is highly dimorphic with males having dark chestnut throat, breast and flanks, and slate upper parts, while females exhibit tawny pale-orange ventral parts, and olivaceous light-brown upper parts; inhabits closed to semi-closed xerop...