Three subspecies recognized:
hirundinaceus, described as Caprimulgus hirundinaceus Spix 1825; type locality Rio Solimoes [error, Feira de Sant' Anna, Bahia, Brazil; Hellmayr 1929: 400)
Northeastern Brazil from Piauí to Alagoas and Bahia. Possibly intergrades with cearae in southern Piauí (Cleere 1998).
See Detailed Description.
cearae, described as Nyctipolus hirundinaceus cearae Cory 1917; type locality Quixada, Ceará, Brazil
Occurs in northeastern Brazil from Ceará to extreme northern Bahia.
Similar to nominate hirundinaceus but paler; the belly more rufous (especially in females) and the underparts not as heavily barred with brown. Undertail coverts are sometimes plain. Males have larger white spots on the four or five outer primaries, and entirely or partially white feather shafts (see Cory 1917 and Cleere 1998).
vielliardi, described as Caprimulgus hirundinaceus vielliardi Ribon 1995; type locality Colatina, Espírito Santo, Brazil
Known from one or possibly two specimens from Espírito Santo (Ripon 1995, Cleere 1998), and from sight records from extreme eastern Minas Gerais (Vasconcelos and Lins 1998).
This is the darkest subspecies, with smaller white spots in the primaries., and with the inner four primaries boldly spotted buff on the upper half of the outerwebs (Cleere 1998).