Taxonomic notes: This species was previously within the genus Phyllomedusa but has recently been moved to the genus Hylomantis (Faivovich et al. 2005). Subsequently, it was moved from Hylomantis to Agalychnis  by Favivovich et al. (2010).

This species occurs in Costa Rica and Panama, and marginally in Colombia. It occurs predominantly on the Atlantic versant from the vicinity of Tilarán, Guanacaste Province, Costa Rica, to western Panama; the disjunct Pacific slope records are from north-western Costa Rica and south-western, central, and extreme eastern Panama in the Darien area, where it extends marginally across the border into Colombia. In Costa Rica the species is now only known with certainty from three sites: Fila Asunción, 15 km south-west of Limón (an abandoned farm); in a forested area near Parque Nacional Barbilla near Siquirres (where one female has been found); and from Guayacán (in Limón Province). All other previously known Costa Rican populations of this species have disappeared including those in Monteverde, San Ramón, Braulio Carrillo, and Tapantí. Its altitudinal range is 440-1,600 m asl. Its range, taken as a proxy for extent of occurrence (EOO), is estimated at 9,273 km².

It is a nocturnal tree frog associated with sloping areas in humid lowland and montane primary forest, and is not found in degraded habitats. The eggs are usually deposited on leaf surfaces and the larvae are washed off or fall into water below the site of oviposition.

It was once considered to be a reasonably common species in Costa Rica, but most populations disappeared in the 1990s. The species is currently known from three different areas in Costa Rica: Cedral, near Miramar, Fila Asunción, Veraguas, and La Alegría, Guayacan. It is still un-recovered in much of its range in Costa Rica, and has not been recorded in recent years in the Cordillera Central or Cordillera de Tilarán.

The species is still considered to be reasonably common in lower elevation in central and eastern parts of Panama (where, for example, there are recent records from Palmarazo), but extensive declines have been recorded in western Panama from the Reserva Forestal Fortuna, Chiriquí (no records from this site since 1999) and El Copé, Coclé (declined from 2004, although it persists at a very reduced abundance [Karen Lips pers. comm. 2007]) (Lips et al. 2006). 

There is no recent population information from Colombia.

There are no reports of this species being utilized.

The massive declines noted in this species are probably due to chytridiomycosis. However, recent studies by Woodhams et al. (2006) found that among the species studied, this was one of the more resistant species to infection with chytridiomycosis; possibly suggesting a reason for the continued persistence of limited numbers of this species at El Copé. General habitat loss and fragmentation also remains a threat, and this is especially the case in Costa Rica where deforestation by squatters threatens Fila Asunción, one of the three known remaining populations.

• 8.1.2 Named species
• 2.1.1 Shifting agriculture
• 2.3.2 Small-holder grazing, ranching or farming
• 5.3.5 Motivation Unknown/Unrecorded
• 2.1.2 Small-holder farming
• 1.1 Housing & urban areas

Within Costa Rica, the former range included several national parks and other protected areas; none of the remaining populations are within national parks (Gerardo Chaves pers. comm. 2007). Therefore, habitat protection is needed for extant population in Costa Rica. Situating barrels of water in the forest successfully attracted this species to reproduce (B. Kubicki pers. comm. August 2010).

The species is known to be present within at least six Panamanian protected areas, but it is not known from any protected areas in Colombia. A successful captive breeding program began in 2001 at the Atlanta Botanical Garden, which has since transferred individuals to other zoos to continue these captive breeding efforts. An ex-situ population of this species is breeding at the El Valle Amphibian Conservation Center in Panama (Edgardo Griffith pers. comm. September 2007).

Research is needed on population distribution, current threats, and population trends.

• 1.1 Site/area protection
• 1.2 Resource & habitat protection

Listed as Critically Endangered because of recent drastic population declines, estimated to be more than 80% over a ten year period (for a given site), inferred from the apparent disappearance of most of the Costa Rican, and some of the western Panamanian population, probably due to chytridiomycosis. Recent declines were recorded at El Copé in 2004, and population declines in western Panama and Costa Rica were documented in the 1990s (Lips et al. 2006).

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