New distributional records of birds from white-sand forests of the northern Peruvian Amazon, with implications for biogeography of northern South America

Ornithological studies in. the Iquitos region of Loreto, Peru, mostly along the Rios Tigre and Nanay, revealed the presence of a previously undetected avifauna restricted to forests growing on ancient white sand or deeply weathered clays, and the blackwater rivers and lakes that drain them. In addition to four species new to science (described elsewhere), eight new species for Peru (Crypturellus duidae, Crypturellus casiquiare, Nyctibius leucopterus, Myrmotherula cherriei, Hemitriccus minimus, Lophotriccus galeatus, Neopelma chrysocephalum, and Xipholena punicea) were documented with tape recordings and specimens. Specimens of two additional species that had only sight or voice records for Peru (Notharchus ordii and Nyctiprogne leucopyga) were also collected. Most represented range extensions of 300-700 km from the blackwater, "sandy-belt" region of far eastern Colombia. We postulate that the western Guianas were the source of ancestral stocks of most contemporary isolates in white-sand habitats in northeastern Peru and eastern Ecuador. We also provide data on several other white-sand and blackwater specialists documented in the study area, and some other birds especially poorly known in Peru.