Clown Frog

The clown frog (Atelopus varius), also known as the harlequin frog or variable harlequin toad, is a small, vibrantly colored true toad in the family Bufonidae native to the premontane and montane rainforests of Costa Rica and Panama. Adults display bold black-and-yellow or black-and-orange aposematic patterns that warn predators of their skin toxins. Males typically measure 27–39 mm in snout-vent length and females slightly larger. The species inhabits fast-flowing streams in humid highland forests at elevations generally between 200 and 1,800 m, where breeding occurs in riparian zones. Atelopus varius was once common throughout its range but has suffered catastrophic population declines since the 1980s, primarily due to the chytrid fungal pathogen Batrachochytrium dendrobatidis (Bd), which has driven mass mortality events in amphibians globally. Additional threats include habitat loss from deforestation and agricultural expansion. The species is listed as Critically Endangered by the IUCN. Conservation programs involving captive breeding and disease-resistant population management are underway in Costa Rica and Panama in collaboration with international zoos.