A New Hybrid Manakin {dixiphia Pipra X Pipra Fiucavda) (aves: Pipridae) from the Andean Foothills of Eastern Ecuador

—A new intergeneric hybrid manakin (Dtxiphia pipra x pipra fiiicauda) is described from the Andean foothills of eastern Ecuador. The adult male specimen represents ihe first record of hybridization among species belonging to different clades of the traditional but polyphyletic genus Pipra (Prum 1990, 1992). The collecting locality, Sarayacu (l°44'S. 77°29"W). apparently lies in a narrow zone ofelevational overlap between the two parental species. The hybrid is nearly intermediate between the parental species in size, plumage pattern, and color. The few documented eases of hybridization in neotropical manakins (Pipridae) have been between species within the same superspecies, or between species in different genera (Parkes 1961, Haflfer 1967, Parsons etal. 1993). Prum"s {1990, 1992) recent revision of the family indicated that the genus Pipra. as currently recognized (e.g., Sibley & Monroe 1990), is polyphyletic, composed of three monophyletic clades (Pipra. Di.xiphi a, Lepidothrix). Hybridization among species belonging to different "Pipra" lineages is unknown and the subject of this paper. An enigmatic manakin was collected by M. Olalla on 21 August 1951, at Sarayacu (1°44'S, 77°29'W; Paynter & Traylor 1977), Provineia de Pastaza, Ecuador. Not clearly assignable to any described species, the specimen (Museo Ecuatoriano de Ciencias Naturales no. 2748) had been variously identified on the tag by ta\onomists as a hybrid (i.e., Pipra filicauda x Chiroxiphia sp.. P. filicauda x Heterocercus sp.. P. filicauda x p. erythrocephala). Analyses of plumage characters and external morphology revealed that none of these hypotheses was correct: the specimen represents a hybrid between Dixiphia pipra (white-crowned manakin) and P. filicauda (wire-tailed manakin). Materials and Methods Sexed as a male, the specimen appears fully mature as judged by its glossy black mantle, wings, and tail. I compared it with series of all species of manakins in the Museo Ecuatoriano de Ciencias Naturales and the National Museum of Natural History, Smithsonian Institution. For the purpose of the hybrid diagnosis (see Graves 1990), 1 considered all species of manakins (n — 16) that occur in western Amazonia and the adjacent Andean foothills of Colombia, Ecuador, and Peru north of the Rio Marafion as potential parental species. Measurements of wing chord, length of central rect rices (= tail), and bill length from anterior edge of nostril were taken with digital calipers. Color comparisons were made under examolilcs (Macbeth Corp.).