Agalychnis lemur, also known as the lemur leaf frog or lemur frog, is a species of frog in the family Phyllomedusidae, also treated as the subfamily Phyllomedusinae in the Hylidae. It is found in Costa Rica, Panama, and adjacent northwestern Colombia. It is classed as Critically Endangered and threatened by the fungal disease chytridiomycosis. Agalychnis lemur lives in tropical mid-elevation pre-montane rainforest between 440 and 1600 metres ASL. Costa Rica is currently host to three sites in which this species resides. They are Fila Asuncion (an abandoned farm 15 km southwest of Limón); a forested area near Parque National Barbilla; and Guayacán in Limón Province. Of these three locations Fila Asuncion is the only one known to have a large breeding population. During the day the Lemur Leaf Frog is a vibrant green but changes to brown at night. This characteristic enhances its ability to camouflage in the day and hunt at night. The Lemur Leaf Frog is a slender species. It has no inter-digital webbing on the front or hind feet. In the past its lack of webbing suggested it belonged in the genus Phyllomedusa. However, recent analysis of mitochondrial and nuclear gene sequences has shown the species was found to genetically closer to species of the genus Agalychnis to which it now belongs This species also displays sexual dimorphism, with the females being larger than males. Adult females range approximately from 40-45mm in length by 15-20mm in length across the abdomen in resting position, while males range from approximately 30-35mm in length by 10-15mm in length across the abdomen. Females on average weigh roughly 4 grams, with males weighing in at half that weight.