Two undescribed species of bird from West Africa

Abstract

Taxonomically undifferentiated western and eastern populations of Dusky Long-tailed Cuckoo Cercococcyx mechowi and Yellow-spotted Barbet Buccanodon duchaillui are known to have very different voices. The cuckoo has two song types, a melodious three-note whistle and a plaintive whinnying in West Africa west of the Bakossi Mountains in Cameroon, and a much less melodious, higher-pitched three-note whistle and a much faster whinnying in Central Africa east of the Bakossi Mountains. The barbet has an accelerating song of some 6.11 hoots west of the Dahomey Gap and a rapid rolling purr to the east. Even though in plumage and morphometrics there is no unambiguous diagnostic distinction between these two vocal groups, analysis of their vocalisations demonstrates a high degree of differentiation. We consider the western groups as species, naming the cuckoo for Francoise Dowsett-Lemaire and the barbet for Robert Dowsett.