Two subspecies currently recognized:

torquata, described as Caprimulgus torquatus Gmelin 1789; type locality Brazil. In some earlier literature, the name brasilianus Gmelin 1789 was widely used, rather than torquata; but the identity of brasiliana is not established, and so torquata assumes priority (Cleere 2002).

This subspecies occupies the northern part of the range of the species, south to eastern Mato Grosso and São Paulo, Brazil.

See Detailed Description.

furcifera, described as Caprimulgus furcifer Vieillot 1817; type locality Paraguay

Breeds from southeastern Peru, eastern Bolivia, and southern Mato Grosso and Paraná, Brazil south to Uruguay and Argentina; partially migratory.

Subspecies furcifera is larger than nominate torquata, and perhaps generally paler, and the nuchal collar usually is buffier (Cleere 1999).

The genus Hydropsalis was proposed by Wagler (1832); the type species, by subsequent designation (Gray 1855: 11), is Caprimulgus furcifer Vieillot.

The genus Hydropsalis currently includes four species: Hydropsalis climacocerca (Ladder-tailed Nightjar), Hydropsalis torquata, Hydropsalis maculicaudus (Spot-tailed Nightjar), and Hydropsalis cayennensis (White-tailed Nightjar). Phylogenetic analysis of DNA sequence data, from both mitochondrial and nuclear genes, indicate that climacocerca and torquata are sister taxa, and that cayennensis is sister to these two (Han et al. 2010, Sigurdsson and Cracraft 2014).