Atelopus varius Lichtenstein and von Martens 1856
Harlequin Frog, Clown Frog, Painted Frog, Veragoa Stubfoot Toad
Atelopus varius has experienced precipitous population declines throughout its range. Populations west of the Canal in Panama have shown drastic declines, and it is nearly extinct in Costa Rica. Chytrid fungus is thought to be the primary cause of its disappearance.
Species description based on Savage (2002).
Medium frog (males 27-39 mm, females 33-48 mm).
Dorsal pattern and coloration extremely variable, but generally consisting of black and one of many colors: bright green, yellow, yellow-orange, or red. Savage (1972) has some excellent photographs showing the range of variation in patterning in this species. The dorsal surface is mostly smooth and lacks any glandular concentrations apparent in some other species of Atelopus.
Ventral surface usually yellow, sometimes mixed with green or red.
Iris green. Pupil horizontal.
In Monteverde, Costa Rica, oviposition takes place during October-December (Savage 2002). In Sante Fe, Panama, an amplectant pair was found in June, but only non-calling males were observed in July (CoCroft et al 1990).
Eggs are laid in two strings and are white (Starret 1967). Eggs are probably affixed to rocks to prevent them from flowing downstream (Starrett 1967). Eggs hatch 6 days after oviposition (Starrett 1967).
The dark brown body is very small, rather flat and looks square from above (Savage 2002). The mouth is very large (Savage 2002). The ventral surface has a large disk that likely serves as a sucker to help tadpoles adhere to rocks in fast-moving water (Savage 2002, Duellman and Lynch 1969). An excellent illustration of the tadpole can be found in Starrett (1967). Tooth rows are 2/3 (Starrett 1967).
Ecology behavior and evolution
Atelopus varius is an ant specialist, but feeds in small amounts on other arthropods (Toft 1981). They actively search for their prey (Toft 1981).
This species is often encountered on rocks in or along the margins of streams (Crump 1986). At night, they sleep on rocks or vegetation (Crump 1986). Population declines have been documented throughout Costa Rica and parts of Panama (Pounds and Crump 1994).
Adult Atelopus varius sometimes become parasitized by flies, which leads to the death of the frog (Crump and Pounds 1985). Frogs are more vulnerable to parasitism during the dry season, when they are forced to aggregate in suitable waterfall spray habitat near streams (Pounds and Crump 1987, Crump and Pounds 1989).
A buzz repeated numerous times (Savage 2002). Atelopus varius also produces chirps that may serve as release calls (Savage 2002). An audiospectrogram of the call can be found in Cocroft et al. (1990).
Behavior and communication
Atelopus varius moves very slowly; presumably the toxins in their skin protect them from potential predators (Crump 1986). During the breeding season, males call to defend territories, but aggressive interactions may escalate to wrestling to establish dominance (Savage 2002). Females are more territorial during the non-breeding season (Savage 2002). This species exhibits homing behavior, returning to the place of capture within a week or less of displacement (Crump 1986).
2N = 22 (Duellman 1967, Schmid 1980)
The skin of Atelopus varius contains tetrodotoxin (Kim et al. 1975).
Taxonomy and systematics
Lichtenstein and von Martens 1856
Atelopus bibronii, Atelopus loomisi, Atelopus varius ambulatorius, Atelopus varius bibroni, Atelopus varius loomisi, Atelopus varius maculatus, Atelopus varius varius, Atelopus varius var. maculatus, Hylaemorphus bibronii, Hylaemorphus dumerilii, Hylaemorphus pluto, Hylaemorphus plutonius, Phrynidium varium, Phrynidium varium var. adspersum, Phrynidium varium var. maculatum, Phryniscus bibronii, Phryniscus dumerilii, Phryniscus varius
"Veragoa". Restricted to "the Pacific portion of the Provincia Veraguas, western Panamá" by Lotters et al (1998)
Habitat and distribution
HabitatMostly found in premontane and montane forest to 2000 m but also on hills in some lowland sites.
Panama. This species has almost gone extinct in Costa Rica.
Distrubution map (IUCN)
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