Voice
A semimusical accelerating trill, becoming louder and more spluttered, often with an introductory note. Often as a duet male first then echoed by female.
Caatinga Antwren (Herpsilochmus sellowi) [XC239937]
by Jeremy Minns from Palmeiras, Chapada Diamantina, Bahia., Brazil (call, song)
Caatinga Antwren (Herpsilochmus sellowi) [XC451826]
by Crizanto B. De-Carvalho from S\u00edtio Pau Preto, Potengi-CE, Cear\u00e1, Brazil (song)
Subspecies
Herpsilochmus pileatus (Sibley and Monroe 1990, 1993) has been split into Bahia Antwren (Herpsilochmus pileatus) and Caatinga Antwren (Herpsilochmus sellowi) following SACC (2005).
Considered part of a clade that also includes Bahia Antwren (Herpsilochmus pileatus), Black-capped Antwren (Herpsilochmus atricapillus), Creamy-bellied Antwren (Herpsilochmus motacilloides) and Ash-throated Antwren (Herpsilochmus parkeri). Present species was long known under name of "Herpsilochmus pileatus", but recent study showing that population of south-eastern Bahia is a distinct species also revealed that this name is actually applicable to the newly discovered form. A replacement scientific name for present species was thus required and supplied.
No subspecies.
Similar Species
Bahia Antwren (Herpsilochmus pileatus) is smaller with a shorter tail. Male also has a grey not white supercilium and lacks the black post-ocular line. Female lacks white streaking on the crown (has some grey scalloping on sides), forehead is greyish, buffy grey on face lacking supercilium and post-ocular stripe.
References
See References.