The most frog-diverse place in Middle America, with notes on conservation status of six threatened species of amphibians

Abstract

Regarding amphibians, Costa Rica exhibits the greatest species richness per unit area in Middle America, with a total of 215 species reported to date. However, this number is likely an underestimate due to the presence of many unexplored areas that are difficult to access. Between 2012 and 2017, a monitoring survey of amphibians was conducted in the Central Caribbean of Costa Rica, on the northern edge of the Matama mountains in the Talamanca mountain range, to study the distribution patterns and natural history of species across this region, particularly those considered as endangered by the International Union for Conservation of Nature. The results show the highest amphibian species richness among Middle America lowland evergreen forests, with a notable anuran representation of 64 species. The greatest diversity in the study area occurred inthe mature forest on the basal belt. Of the 68 amphibian species found, seven (10%) are endemic to the Atlantic versant and eight (11.6%) are threatened. This survey includes the first record of Gastrotheca cornuta in Costa Rica since it was last reported 21 years ago. New populations of Agalychnis lemur (Critically Endangered) and Duellmanohyla uranochroa (Endangered) are reported, and Ecnomiohyla veraguensis (Endangered) is reported for the first time in Costa Rica. These findings show that this locality is a high priority conservation area for a large number of amphibian species, which are often threatened by habitat loss and fragmentation.