Biogeographic Oddity in a Disappearing Ecosystem: A New Glassfrog (Centrolenidae: Nymphargus) From the Ecuadorian Chocó

Nymphargus is a genus of glassfrogs primarily known from the Andes. The discovery of a Nymphargus species in the lowland Chocó region represents a biogeographic oddity. Herein we describe this new taxon based on the following main traits: (i) absence of hand webbing, (ii) green dorsum with numerous black flecks and scarce yellow false ocelli, (iii) absence of vomerine teeth, and (iv) relatively large body size (SVL > 30 mm). Despite extensive subsequent herpetological efforts in the area, no additional specimens have been found, underscoring its rarity and vulnerability. Given its limited range in the Chocó ecoregion and the ongoing threats of habitat destruction (i.e., logging, agricultural expansion, mining), we classify this new taxon as Critically Endangered, according to IUCN criteria. Lastly, we analyzed the forest cover of the Ecuadorian Chocó during 1985–2022; during this time period 194,007 hectares have been deforested, representing a 20 % destruction of the original ecosystem. We estimate that an average of 5,243 hectares of forest are lost annually; this data highlights the urgency for conservation actions in the Chocó.