Atelopus is a large genus of true toads, commonly known as harlequin toads or stubfoot toads, from Central and South America, ranging as far north as Costa Rica and as far south as Bolivia. Atelopus species are small, generally brightly colored, and diurnal. Most species are associated with mid-to-high elevation streams. This genus has been greatly affected by amphibian declines, and many species are now considered endangered, while others already are extinct. Almost 40% of the described species in the genus are considered possibly extinct; this is raised to 45% when data deficient species are added; this number may be even higher, given that the genus contains many undescribed species that could also be extinct, and many of the species considered critically endangered but extant may have gone extinct after the last surveys that detected them, or could go extinct in the future. While threatened by habitat loss, pollution, and introduced species, the primary cause of these declines appears to be the chytrid fungus Batrachochytrium dendrobatidis. For example, there are 32 known Atelopus species in Ecuador. One of these is data deficient, two are endangered and the remaining are critically endangered. Almost half the Ecuador species have not been recorded in a decade or more and are likely extinct. In some species conservationists have established captive colonies as a safeguard. However, numerous Atelopus species have been rediscovered decades after their last sighting, such as A. arsyescue, A. mindoensis, A. bomolochos, A. ignescens, A. balios, A. longirostris, A. subornatus and A. varius.
The Panamanian golden frog, also known as Cerro Campana stubfoot toad and other names, is a species of toad endemic to Panama. Panamanian golden frogs inhabit the streams along the mountainous slopes of the Cordilleran cloud forests of west-central Panama. While the IUCN lists it as critically endangered, it may in fact have been extinct in the wild since 2007. Individuals have been collected for breeding in captivity in a bid to preserve the species. The alternative common name, Zetek's golden frog, and the epithet zeteki both commemorate the entomologist James Zetek.
Atelopus varius, the Costa Rican variable harlequin toad or clown frog, is a small Neotropical true toad from the family Bufonidae. Once ranging from Costa Rica to Panama, A. varius is now listed as critically endangered and has been reduced to a single remnant population near Quepos, Costa Rica and has only relict populations in western Panama (IUCN). Recent variation in air temperature, precipitation, stream flow patterns, and the subsequent spread of a pathogenic chytrid fungus (Batrachochytrium dendrobatidis) linked to global climate change have been the leading cause of decline for A. varius. A. zeteki has been considered a subspecies of A. varius, but is now generally considered a separate species.
Atelopus andinus, sometimes known as the Andes stubfoot toad, is a species of toad in the family Bufonidae. It is endemic to eastern Peru. It inhabits submontane tropical primary and riparian forests at elevations of 1,000–2,200 m (3,300–7,200 ft) above sea level.
Atelopus balios, the Rio Pescado stubfoot toad, is a species of toad in the family Bufonidae. It is endemic to southwestern Ecuador, with records from Pacific lowlands in Azuay, Cañar, and Guayas Provinces. It is a rare species that was already suspected to be extinct, but a single specimen was discovered in 2011 by a team from Conservation International during a hunt for missing amphibians. The decline in amphibian populations is well documented. The Atelopus balios is Critically Endangered as a result of the widespread amphibian Chytridiomycosis fungus that has decimated other amphibian populations. There are only 10 known findings of the tadpole, Atelopus balios.
The Guajira stubfoot toad or Carrikeri harlequin frog, Atelopus carrikeri, is a species of toad in the family Bufonidae. It is about 5 cm (2.0 in) long and typically black, though some populations have orange coloration. This species is endemic to the Sierra Nevada de Santa Marta mountain range of northern Colombia. It is critically endangered because of the chytrid fungus, Batrachochytrium dendrobatidis, and habitat destruction due to agriculture. The species had not been seen from 1994 until it was rediscovered in early 2008.
Atelopus chiriquiensis, the Chiriqui harlequin frog or Lewis' stubfoot toad, is an extinct species of toad in the family Bufonidae that was found in the Cordillera de Talamanca in Costa Rica and western Panama. Its natural habitats were stream margins in lower montane wet forests and rainforests. Its elevational range was 1,400–2,500 m (4,600–8,200 ft) asl.
Atelopus exiguus is a species of toad in the family Bufonidae. It is endemic to Ecuador and only known from the area of its type locality in the Azuay Province of southern Ecuador, in the sub-páramo and páramo of Cordillera Occidental. Common name Mazán jambato frog has been proposed for it.
Atelopus limosus, the limosa harlequin frog is an endangered species of toad in the family Bufonidae endemic to Panama. Its natural habitats are stream banks in tropical moist lowland forests and rivers of the Chagres watershed in central Panama.
Atelopus pachydermus is a species of toad in the family Bufonidae. It is found in the Andes of northern Peru and southern Ecuador. Records from Colombia reflect the vagueness of the stated type locality, "Neu-Granada", encompassing territory part of several present-day countries. Other records outside the current range refer to other species. The most recent record of this very rare and possibly extinct species is from around 1995. However, there is a need to reassess the status of this species because of confusion with Atelopus podocarpus.
Atelopus pulcher is a species of toad in the family Bufonidae. It is endemic to eastern Peru where it is found in the Huallaga River drainage; its range might extend to Ecuador. Its natural habitats are lowland and premontane tropical forests. It is a diurnal and terrestrial species that breeds in streams.
The three-coloured harlequin toad is a species of toad in the family Bufonidae. It is found in Bolivia and Peru. Its natural habitats are subtropical or tropical moist montane forests and rivers. It is threatened by habitat loss.
Atelopus petersi is a species of toads in the family Bufonidae. It is endemic to Ecuador and is known from the Cordillera Oriental in the Napo Province and more provisionally, in the Chimborazo Province. The specific name petersi honors James A. Peters, an American zoologist who collected the first specimens of this species in 1962 and provided a description under the name Atelopus pachydermus. Common names Peters' stubfoot toad and Peters' jambato toad have been coined for it.
Atelopus patazensis is a species of toads in the family Bufonidae. It is endemic to Peru and only known from its type locality in Quebrada Los Alisos, near Pataz in the La Libertad Region. There is, however, an unverified observation from Llacuabamba, about 40 km south of Pataz.
Atelopus onorei is a small species of bright yellow and green toads in the family Bufonidae. It is endemic to Ecuador and is only known from the vicinity of its type locality on the western slope of the Cordillera Occidental in the Azuay Province. It has not been seen since 1990 and may now be extinct, but it is possible that overlooked populations remain.
Atelopus pyrodactylus is a species of toad in the family Bufonidae. It is endemic to Peru and only known from its type locality in the northern section of the Río Huallaga basin, Department of San Martín, on the eastern slope of the Cordillera Central. The specific name pyrodactylus refers to the light orange fingers and toes of this frog.
María Cristina Ardila-Robayo was a Colombian herpetologist. She was professor at the National University of Colombia, Bogotá, and worked closely with the Natural History Museum of the university. In 2010 she was credited as having described 28 new species of amphibians from Colombia; as of late 2018, the Amphibian Species of the World lists 31 valid species described by her. She also worked with caimans and crocodiles and lead biodiversity restoration projects.
Atelopus ardila is a species of frog in the family Bufonidae. It has not been seen since 1992, and is believed to be possibly extinct.
Atelopus pastuso is a species of frog in the family Bufonidae. It has not been seen since 1993, and is possibly extinct.
Atelopus podocarpus is a species of frog in the family Bufonidae. It has not been seen since 1994, and is believed to be possibly extinct.
