The “Colostethus” ruthveni group represents an endemic dendrobatid lineage in the Sierra Nevada de Santa Marta (SNSM), an isolated massif in northeastern Colombia. This group has a complex taxonomic history and comprises the nominal species, from the northern and northwestern sector of the SNSM and an undescribed morph provisionally named as “Colostethus” sp. ruthveni-like, from the southeastern sector of this mountain massif. Herein, we describe the advertisement calls of members of the “C.” ruthveni group from several