A new, toxic species of Colostethus (Anura: Dendrobatidae: Colostethinae) from the Cordillera Central of Colombia

Abstract

A new species of Colostethus is described from cloud forest in the Cordillera Central of Colombia at approximately 2100–2500 m above sea level. It is a riparian species not known to occur more than a few meters from the water’s edge. Specimens were collected in grassy vegetation and on and beneath rocks along streams and pools, in both primary forest and in or at the edge of forest clearings. Most specimens were collected during the day, but several were observed to be active at night. The new species differs from other species of Colostethus in lacking pale oblique lateral and ventrolateral stripes, possessing a pale dorsolateral stripe, lacking or having at most rudimentary toe webbing, and possessing a marbled or reticulated ventral color pattern. Adult males of the new species possess a swollen third finger and a gray or black throat. In life, the new species possesses bright lemonor golden-yellow flash marks on the axilla, groin, belly, and concealed surfaces of the thigh and shank, and bluish-white ventral coloration, and it exudes a milky secretion from the skin. The aqueous extract of the skin is toxic, but additional samples are required to determine the nature of the toxic compound(s).