All these species, except for the rufous-shafted woodstar, were formerly placed in the genus Acestrura.[5] In 1999 Karl-Ludwig Schuchmann remarked in the Handbook of the Birds of the World that for the species placed in Acestrura: "...no evidence in external morphology justifies treatment in a genus separate from C. jourdanii".[6]
^Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (August 2022). "Hummingbirds". IOC World Bird List Version 12.2. International Ornithologists' Union. Retrieved 16 September 2022.
^Schuchmann, K.L. (1999). "Genus Chaetocercus". In del Hoyo, J.; Elliott, A.; Sargatal, J. (eds.). Handbook of the Birds of the World. Vol. 5: Barn-owls to Hummingbirds. Barcelona, Spain: Lynx Edicions. p. 677. ISBN978-84-87334-25-2.