Systematics

Because Long-tailed Manakins have a continuous range that is unbroken by such geographical features as large rivers and mountains, the variation among the species is low (McDonald 2003). Two subspecies of Long-tailed Manakin often are recognized, nominate linearis of southern Mexico and Guatemala, and fastuosa from southern El Salvador to northwestern Costa Rica (Snow 2004). Purportedly linearis has less elongated central rectrices, and a larger and broader bill (Bangs and Peters 1928). Bangs and Peters (1928) asserted, rather than documented, these differences, however, and later authors have found extensive overlap in measurements between northern and southern populations (Monroe 1968, Kirwan 2011). Consequently Long-tailed Manakin is better regarded as monotypic.

Phylogenetic relationships within Chiroxiphia have not been investigated. Snow (1975, 1979) classified as a superspecies the four then-recognized species: linearis, lanceolata (Lance-tailed Manakin), pareola (Blue-backed Manakin), and caudata (Swallow-tailed Manakin).

Phylogenetic relationships of the genera within Pipridae remain unresolved. A sister-group relationship between Chiroxiphia and Antilophia, however, is recovered consistently in phylogenetic studies, based on syringeal morphology (Prum 1992) and on phylogenetic analyses of DNA sequence data from both mitochondrial and nuclear genes (Rego et al. 2007, Tello et al. 2009, McKay et al. 2010).