Small, mouse-like bird found in cloud forest understory in Colombia’s Santa Marta Mountains. Adult male is gray with a white crown patch and rusty barring on the lower underparts. Female is washed with brown, and young birds have a lot of scaling and barring. The only other tapaculo in the Santa Martas is Brown-rumped Tapaculo, which lacks white in the crown, occurs at higher elevations, and has a different voice. Typical song is a very fast trill that lasts for at least ten seconds and may continue for a minute or more.