This species is known from 1,100-1,220m asl on Cerro Las Flores, a semi-isolated uplifted area that is part of the fragmented Sierra Mixe, in south-central Oaxaca, Mexico. Many hylids in this region have been found to be localized endemics.
Habitat and Ecology
This species is recorded from cloud forest. One individual was found on vegetation 1.8m above a small stream. Tadpoles were found in pools in this stream, which contained little flowing water at the time, and coursed through large boulders at the bottom of a deep ravine. Tadpoles were found in several similar streams nearby.
No information is currently available on the species' population status, but it is possible that is has undergone a serious decline due to chytridiomycosis, and the only known population might already be extinct.
The primary threat to the species is habitat loss, and large expanses of forest are being cleared in this region. In addition, many of the tadpoles found at Cerro Las Flores possessed deformed or missing mouthparts, which might indicate infection with chytridiomycosis. Indeed, the specific name of this species is derived from the Greek ephemeros, meaning shortlived, referring to the ominous observation that chytridiomycosis might be present.
The species is not known from any protected areas, and protection and maintenance of remaining habitat in the region is urgently required. It is a very high priority to conduct surveys to relocate this species and determine its current population status and whether or not it is still extant; in view of the threat of chytridiomycosis, any surviving individuals would need to form the basis for a captive-breeding programme.
This species was previously included in the genus Hyla but has recently been moved to the genus Plectrohyla (Faivovich et al. 2005).
Joseph Mendelson III 2006. Plectrohyla ephemera. In: IUCN 2014