Six subspecies of Rufous-tailed Jacamar currently are recognized:
Galbula ruficauda ruficauda: Described by Cuvier in 1817, with a type locality of Guiana. Occurs in northern Colombia from the Cauca and Magdalena valleys east to northern Brazil and the Guianas, and on Trinidad and Tobago.
Characters as in the Detailed Description.
Galbula ruficauda melanogenia: Described by Sclater in 1852, with a type locality of Veragua. Occurs from southern Mexico south to western Panama, and from eastern Panama south to western Colombia and Ecuador.
Differs from nominate ruficauda by having four (not two) central rectrices green, and a black chin. Hybridizes with nominate ruficauda in northwestern Colombia.
Galbula ruficauda pallens: Described by Bangs in 1898, with a type locality of Santa Marta, Colombia. Occurs in northern Colombia, from the Río Sinú east to Guajira.
Similar to nominate ruficauda, but has paler underparts, especially in the female; green breast band narrower; and bill longer. Variation from ruficauda is clinal.
Galbula ruficauda brevirostris: Described by Cory in 1913, with a type locality of Encontrados, southwest of Lake Maracaibo, Venezuela. Distribution is limited to the head of the Maracaibo basin.
Similar to nominate ruficauda, but paler, and has a shorter bill. Variation from ruficauda is clinal.
Galbula ruficauda rufoviridis: Described by Cabanis in 1851, with a type locality of Brazil. Occurs in Brazil south of the Amazon, Paraguay, northern Bolivia (Beni), and northeastern Argentina.
Differs from nominate ruficauda by having four (not two) central rectrices green. Also, the outer webs of the tips of the outer rectrices green.
Galbula ruficauda heterogyna: Described by Todd in 1932, with a type locality of Palmarito, Río San Julián, Chiquitos, Bolivia. Occurs in eastern central Bolivia and in western Mato Grosso, Brazil.
Similar to rufoviridis, but paler. Variation with rufoviridis is clinal.
Descriptions of the subspecies are based on Haffer (1974) and Tobias et al. (2002). Ranges of the subspecies are based on Peters (1948).