The Chocó vireo was first observed on August 25, 1991, by Paul Salaman in western Nariño located in southwest Colombia.

[4] The site, located at an altitude of 1,500 meters (five thousand feet), was in a narrow strip of intact, very wet forest along the Rio Nambi, in the Chocó region which is famed for its high biological diversity.

In early June, 1992, ornithologist Gary Stiles observed and collected this species while working in Alto de Pisones in Risaralda department.

The bird was small, a little more than four inches, lightweight at 11.4 grams, and greenish in color with a broad, wide yellowish wing bar.

Bernard Master, the first American birder to have seen a representative of every bird family in the world, won the auction with a bid of US$75,000 and named it Vireo masteri.