Abstract
Creagrutus yanatili, new species, is described from the Río Urubamba drainage, southeastern Perú. It is most similar to C. peruanus, with which it occurs at one of the two known collecting localities, with respect to overall body form and meristic characters. Creagrutus yanatili differs from other Creagrutus species in the region and nearly all other Creagrutus species in the presence of very well developed papillae extending posterior of the head over most of the predorsal surface, and from all other described Creagrutus species in the presence of very dark, nearly black, pigmentation covering much of the body and fins, and the presence of both straight, needle-like and hook-like contact organs on the shafts of the anal-fin rays.
