Another Amazonian cryptic species split

Blackish Antbird Cercomacra nigrescens is a widespread lowland South American bird from the family Thamnophilidae. The 200 species of this insectivorous family seem to conceal many cryptic species. 

C n fuscicauda, found in the borderlands of Peru, Colombia, Ecuador, Brazil and Bolivia, has been found to produce a very distinctive song and is apparently reproductively isolated where it meets the ranges of other subspecies. Thus, it has been deemed a new species, now named Riparian Antbird.

For more information on this, see: Mayer, S, Coopmans, P, Krabbe, N, and Isler, M L.  2014.  Vocal evidence for species rank to Cercomacra nigrescens fuscicauda J. T. Zimmer. Bulletin of the British Ornithologists' Club 134: 145-154.