Batrachochytrium salamandrivorans (Bsal) is a virulent fungal pathogen that infects salamanders. It is implicated in the recent collapse of several populations of fire salamanders in Europe. This pathogen seems much like that of its sister species, Batrachochytrium dendrobatidis (Bd), the agent responsible for anuran extinctions and extirpations worldwide, and is considered to be an emerging global threat to salamander communities. Bsal thrives at temperatures found in many mountainous regions rich in salamander species; because of this, we have screened specimens of salamanders representing 17 species inhabiting mountain ranges in three continents: The Smoky Mountains, the Swiss Alps, and the Peruvian Andes. We screened 509 salamanders, with 192 representing New World salamanders that were never tested for Bsal previously. Bsal was not detected, and Bd was mostly present at low prevalence except for one site in the Andes.

We report recent findings of Isthmohyla pictipes (Cope, 1875) in the Cordillera de Talamanca, Costa Rica, roughly two decades after it was last registered. We provide notes on microhabitat use, color variation, external morphology of adults and larvae, and geographic variation, and discuss some taxonomic characters employed to differentiate I. pictipes from I. tica (Starrett, 1966) and I. xanthosticta (Duellman, 1968). We also report fluorescence on the ventral surfaces of I. pictipes. Our findings are expected to shed light on the taxonomy of this species and should be useful in further population assessments and conservation plans.

Treefrogs represent 22% of amphibian species in Costa Rica, but gaps in the knowledge about this group of amphibians can impede conservation efforts. In this study, we first updated the status of Costa Rican treefrogs and found that a total of 38% of treefrog species are threatened according to the most recent IUCN assessment in 2019. Additionally, 21% of Costa Rican treefrog species have a high vulnerability to extinction according to environmental vulnerability scores. Then, we predicted the historical climatic suitability of eight target species that we expected to have exhibited changes in their ranges in the last 20 years. We assessed the location of new occurrence records since 2000 to identify recovery, range expansion, or previously underestimated ranges due to methodological limitations. We also estimated the area of each species’ suitable habitat with two metrics: extent of suitable habitat (ESH) and area of minimum convex polygon (A_MCP). Six declined species exhibited recovery (i.e., new occurrences across historical range after 2000), with the widest recovery found in Agalychnis annae. We also found that Isthmohyla pseudopuma appears to have spread after the decline of sympatric species and that the range of I. sukia was originally underestimated due to inadequate detection. We found that the ESH was 32–49% smaller than the A_MCP for species that are slowly recovering; however, the ESH is similar or greater than the A_MCP for species that are recovering in most of their ranges, as well as rare species with widespread ranges. Results of this work can be used to evaluate the risk of environmental threats and prioritize regions for conservation purposes.

A new species of hylid frog is described from Tapir Valley Nature Reserve, located on the Caribbean slope of Tenorio Volcano in Bijagua, Alajuela Province, Costa Rica. A molecular phylogenetic analysis supports its inclusion in the genus Tlalocohyla. Morphological, morphometric, larval, and acoustic characteristics further distinguish it from other species in the genus and support its uniqueness. The new species is closely related to T. picta and T. smithii, and is separated by at least 500 kilometers from the nearest known occurrence of a population of T. picta in southern Honduras. The new species is readily distinguished from all other Tlalocohyla by its brilliant green coloration marked with a pronounced, incomplete light dorsolateral stripe that is bordered above by a diffuse reddish-brown stripe. Its dorsum is marked with bold reddish brown spots and its ventral skin is fully transparent. This new Tlalocohyla is currently only known from the type locality, where it inhabits a lentic wetland system with an emergent herbaceous vegetation-dominated benthic zone, surrounded by tropical rainforest. A description of its bioacoustic repertoire and information on natural history, reproduction and habitat preference of this new species are provided.