Atelopus varius

The historic range of A. varius stretched from the Pacific and Atlantic slopes of the Cordilleras de Tilaran mountain range in Costa Rica into western Panama. Suitable habitat includes both pre-montane and lower-montane zones as well as some lowland sites along rocky streams in hilly areas (ranging from in elevation). == Habitat and ecology ==

A. varius is a diurnal frog often found on rocks or in crevices along streams in humid lowland and montane forests. It is primarily a terrestrial species, only entering the water during breeding season, relying on spray from streams for moisture. The Costa Rican variable harlequin frog is slow moving and often remains in the same area for long periods of time. The conspicuous or aposematic coloration of A. varius likely serves as a warning to potential predators of the toxicity of the frog's integument which contains tetrodotoxin, a potent neurotoxin. The only known predator of A. varius is a parasitic sarcophagid fly Notochaeta bufonivora which deposits its larvae on the surface of the frog's thigh. The larvae then proceed to burrow inside the frog and eat it from within. == Conservation status ==

In recent decades, A. varius has become increasingly rare throughout its geographic range. The first incidence of its disappearance was recorded after a census conducted between 1990 and 1992 near Monteverde, Costa Rica revealed zero individuals where its population had previously peaked at 751 adults. however the species was recorded again in the 2019 assessment. More recently, an observed global decline in amphibian species richness has been linked to an outbreak of the pathogenic chytrid fungus Batrachochytrium dendrobatidis. == References ==