Tadpoles of the genus Smilisca are of a generalized hylid type, having 2/3 tooth-rows, unspecialized beaks, mouth partly or completely bordered by papillae, lateral fold present in the lips, spiracle sinistral, anal tube dextral, and caudal musculature extending nearly to tip of caudal fin. Although minor differences exist in coloration, proportions, and mouthparts, no great modifications of the basic structure are present.
The larval characters of the species of Smilisca are compared below and illustrated in Figures 11-15.
Shape and Proportions.—The bodies of S. baudini, cyanosticta, phaeota, and puma are rounded and about as wide as deep; the eyes are moderately large and directed dorsolaterally, and the nostrils are about midway between the bluntly rounded snout and the eyes. The mouths are medium-sized and directed anteroventrally. The bodies of tadpoles of S. sila and sordida are slightly compressed dorso-ventrally. The snout is moderately long and sloping; the eyes are larger and directed more dorsally than in the other species, and the nostrils are closer to the eyes than the snout. The mouths are moderately large and directed ventrally.
The tail is about half again as long as the body in S. baudini, cyanosticta, phaeota, and puma; in these species the caudal musculature is moderately heavy, and the caudal fins are deep. The caudal musculature is upturned distally in S. baudini and phaeota, and the dorsal fin extends anteriorly onto the body in these two species and in S. puma. The tail is about twice as long as the body in S. sila and sordida. In both species the caudal fins are shallow in comparison with the depth of the caudal musculature, especially in S. sordida (Fig. 14); in neither species does the dorsal fin extend anteriorly onto the body.
Fig. 11. Tadpoles of Smilisca baudini: (A) Stage 21 (KU 62155) × 10; (B) Stage 25 (KU 68467) × 5; (C) Stage 30 (KU 60018) × 4; (D) Stage 41 (KU 60018) × 3.
Mouthparts.—The mouth of S. sordida is completely bordered by two rows of papillae, whereas in the other species the median part of the upper lip is devoid of papillae. Smilisca baudini and puma have two rows of papillae; S. sila has one complete row (except medially on the upper lip) and one incomplete row, and S. cyanosticta and phaeota have only one row (Fig. 15). All species have numerous papillae in the lateral fold; the fewest lateral papillae are found in S. cyanosticta and phaeota. Although all species have two rows of teeth in the upper jaw and three rows in the lower jaw, specific differences in the nature of the rows exist between certain species. The second upper tooth-row is narrowly interrupted medially in S. sila and sordida and broadly interrupted in the other species. The first upper row is strongly arched in S. puma, moderately arched in S. baudini and sila, and weakly arched in the other species. In all species the third lower tooth-row is the shortest, only slightly so in S. sila and sordida, but only about half the length of the second lower row in S. puma.