A new amazonian species of Colostethus (Anura: Dendrobatidae) with a nidicolous tadpole

Abstract

We describe adults, tadpoles, and vocalization of a new Amazonian species of Colostethus from a terra firme rainforest locality south of the Amazon River near Manaus, Amazonas, Brazil. This species is characterized by the absence of dorsolateral and ventrolateral stripes, the presence of a short, diffuse oblique lateral stripe, Finger III of male not swollen, and the presence of a black or gray throat in the male. In addition, the new species is larger than three other species in the Amazon region (C. caeruleodactylus, C. marchesianus, and C. stepheni) and its call, typically composed of long bouts of continuous notes, is distinct from these three species. This species is the fourth known Colostethus with an endotrophic tadpole; in three of these species, including C. nidicola, eggs are deposited and develop entirely in a terrestrial nest. Clutches of C. nidicola are composed of about three eggs and are placed in leaf litter on the forest floor. Whether C. nidicola is closely related to any of the other three species with endotrophic tadpoles is unknown at present. A phylogenetic analysis of this group of frogs will be necessary to detect whether endotrophy has evolved once or multiple times. Examination of tadpoles of C. nidicola and comparisons with characters reported for the other three species that have endotropic tadpoles revealed that tadpoles within each species have unique combinations of characters or loss of characters. Endotrophic tadpoles have not been reported for any other dendrobatids.