This is a medium to large frog, moderately robust and squat with stout limbs. This species shows sexual dimorphism in size with the females substantially larger than then males, (the females can become almost twice the size of the males). They have a rounded blunt snout; the canthus rostralis is rounded and the loreal region is slightly concave. The tympanum is much smaller than the eye in this species and there is a supratympanic fold. They have expanded tips on both the fingers and toes, and the toes are moderately webbed. Males of this species do not have vocal slits or nuptial pads. The dorsum is granular and is usually a dark gray, brown or a reddish brown, usually with some indistinct darker spots and blotches. Some individuals have a narrow, light vertebral stripe. The venter is lighter than the dorsal coloration and is usually white, cream or yellow. The throat may often show some dark pigmentation. Some specimens show dark bars on the lips. The posterior regions of the thighs shows distinct patterns of light spots on a dark background (description from Lee1996).
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Mexico
"Occurs at low to moderate elevations from southern San Luis Potosi on the Atlantic slope and central Guerrero on the Pacific slope, east and southward through Central America to Western Panama" (Lee1996). They prefer rocky streams in forested areas. They can be found on the forest floor but usually found perched on rocks in and around the water (Lee1996).
Life History, Abundance, Activity, and Special Behaviors
Generally nocturnal in nature they eat mainly invertebrates, particularly insects. This is an oviparous species, the eggs are laid in moist soils and undergo direct development (from Lee 1996).
The specific name rugulosus, is a diminutive of the Latin, rugosus, meaning "wrinkled", referring to the rough surface skin on the dorsum (from Lee1996).
Lee, J. C. (1996). The Amphibians and Reptiles of the Yucatan Peninsula. Cornell University Press, Ithaca, New York.
Written by Amy Jess (amyj AT uclink4.berkeley.edu), University of California, Berkeley
First submitted 1999-06-02
Edited by Meredith J. Mahoney (2007-11-30)
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Citation: AmphibiaWeb: Information on
amphibian biology and conservation. [web application]. 2016. Berkeley, California:
(Accessed: Jul 28, 2016).
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