Small stocky frog with relatively large head. Adults of both sexes obtain a snout-vent length of about 55 mm. The eyes are large and have a vertical slit-shaped pupil. Parotid glands are small, and the tympanum is mostly visible. The skin is warty, and a row of large, often reddish warts extends from the tympanum to the loin area. Other large gland complexes are present on the underarms and the ankles. There are three metacarpal tubercles. The coloration can vary from small black dots, brown dots to olive or green spots. The underside is a dirty white, and the throat and the chest are often spotted with gray (Noellert and Noellert 1992).

Males are somewhat smaller than females. Other features that distinguish males and females are: distance between nostrils, distance between the anterior end of the middle metacarpal tubercle and the tip of the third finger, and the distance from the elbow to the third finger tip. These variables should be corrected for the size of the animal (Bosch and Marquez 1996).