Fan-tailed Warbler

About the Fan-tailed Warbler

The fan-tailed warbler (Basileuterus lachrymosus) is a species of bird in the family Parulidae, the New World warblers. It is found from Mexico to Nicaragua. It has also been recorded as a vagrant in the U. S. states of Arizona, New Mexico, and Texas. Its "habit of constant tail-fanning and tail-swinging [is] distinctive".

The fan-tailed warbler has a complicated taxonomic history that as of July 2026 has not been resolved. Its formally description in 1850 with the binomial Sylvia lachrymosus is credited to Charles Lucien Bonaparte. However, Bonaparte appended "(Basileuterus? lachrymosus, Cabanis)" to the binomial. Cabanis had not published the name and so is not credited with the description despite the species' later assignment to his genus. In 1850 Cabanis had also erected genus Euthlypis, and in 1902 Robert Ridgway assigned the fan-tailed warbler to it, retroactively declaring it the type species of the genus.

A molecular phylogenetic study published in 2010 found that the fan-tailed warbler was basal to the genus Basileuterus. Based on the study, in 2011 taxonomic systems began reassigning it to that genus. As of July 2026 the IOC, BirdLife International... Wikipedia →