This species is endemic to the western Cordillera Central of Panama at elevations of 1,120-1,650 m asl on both sides of the continental divide in the western part of the Serranía de Tabasará and on the Pacific slopes of the eastern part of the Cordillera de Talamanca. It has not been recorded from Costa Rica, but may be present in this country. Its range, taken as a proxy for extent of occurrence (EOO), is estimated at 1,875 km
Habitat and Ecology
It is an arboreal species that inhabits humid montane forest, small ponds, puddles, and low-gradient streams. Breeding occurs in these aquatic habitats.
The population of this species has declined drastically (Lips 1999) and has disappeared from all previously known sites. However, in 2010, five individuals were collected in western Panama and several calling males were detected at what is the only known extant population (Hertz et al. 2012).
Infection by the chytrid pathogen was recorded by Lips (1999) at the Reserva Forestal Fortuna, in Chiriquí, and this is probably the most serious threat to the species. It is also threatened by deforestation resulting from cattle ranching, small-holder agriculture, and road construction (A. Hertz pers. comm. 2013).
In the past, the species has been recorded in a number of protected areas, including Parque Nacional Santa Fe, Parque Internacional La Amistad, and the Reserva Forestal Fortuna. However, there have been no recent records in these protected areas (Hertz et al. 2012). The only known extant population occurs in Cerro Colorado, which is not within a protected area. This species is an urgent priority for survey work. In view of the threat of chytridiomycosis, surviving individuals might need to form the basis for the establishment of an ex-situ population.
This species was previously included in the genus Hyla but has recently been moved to the new genus Isthmohyla (Faivovich et al. 2005).
IUCN SSC Amphibian Specialist Group & NatureServe 2014. Isthmohyla graceae. In: IUCN 2014