| Table 10.—Growth and Development of Tadpoles of Smilisca cyanosticta. (Means Are Given in Parentheses After the Observed Ranges.) | ||||
| Stage | N | Total length | Body length | Tail length |
| 21 | 10 | 5.8-6.5 (6.28) | 2.8-3.1 (3.00) | 3.0-3.5 (3.28) |
| 25 | 10 | 7.9-9.2 (8.44) | 2.7-3.2 (2.96) | 4.8-6.0 (5.48) |
| 30 | 7 | 22.5-25.0 (23.50) | 8.5-9.5 (9.00) | 14.0-15.5 (14.57) |
| 36 | 10 | 27.0-30.0 (28.75) | 9.5-11.5 (10.80) | 17.0-18.5 (17.95) |
| 42 | 2 | 26.0-27.0 (26.50) | 10.00 | 16.0-17.0 (16.50) |
| 46 | 2 | — | 14.00 | — |
Hatchlings of three species (S. baudini, cyanosticta, and phaeota) are available. These larvae have non-functional eyes and large oral suckers. By the time the larvae have developed to stage 21, external gills are present, the caudal musculature and caudal fin have been differentiated, and the head is distinguishable from the body. In stage 21 oral suckers and a large amount of yolk are still present.
The developmental data on the four species show no significant variations; consequently, we will describe the development of only one species, Smilisca phaeota (Table 11, Figs. 13 and 16).
Stage 21.—Bulging cream-colored yolk mass, transparent cornea, and moderately long, unbranched filamentous gills, and oral suckers present; mouth having irregular papillae on lower lip; teeth and beaks absent; caudal myomeres distinct; pigmentation uniform over body and caudal musculature; caudal fin transparent with scattered small flecks.
Fig. 16. Relative rate of growth in tadpoles of Smilisca phaeota as correlated with developmental stages. Formulas for the limb bud refer to its length (L) in relation to basal diameter (D).
Stage 25.—Operculum complete; gills absent; sinistral spiracle apparently functional; cloacal tail-piece, nasal capsules, and external nares present; gut partly formed; mouth bordered by single row of papillae, except medially; small papillae present in lateral fold of lips; two upper and three lower tooth-rows present, but not fully developed; beaks apparently fully developed; depth of dorsal and ventral fins less than depth of caudal musculature: tip of tail upturned; pigment on body most dense on dorsum and sides; faint, nearly pigmentless crescent-shaped mark on posterior edge of body; concentrations of pigment forming small spots on tail.
Stage 28.—Mouthparts complete; limb bud about half as long as thick; other structural features and coloration closely resemble those in stage 25.
Stage 30.—Limb bud approximately twice as long as thick; body as deep as wide; dorsal fin deepest just posterior to body; ventral fin deeper than caudal musculature; tail sharply upturned distally; anal tube dextral; brown pigment sparse on flanks.
| Table 11.—Growth and Development of Tadpoles of Smilisca phaeota. (Means Are Given in Parentheses After the Observed Ranges.) | ||||
| Stage | N | Total length | Body length | Tail length |
| 15 | 10 | — | 1.9-2.1 (1.97) | — |
| 16 | 8 | — | 2.0-2.2 (2.07) | — |
| 18 | 4 | — | 2.2-2.6 (2.31) | — |
| 21 | 3 | 7.9-8.6 (8.21) | 4.1-4.5 (4.31) | 3.8-4.1 (3.92) |
| 25 | 10 | 8.7-10.6 (9.69) | 4.5-4.8 (4.64) | 4.3-6.0 (5.05) |
| 26 | 11 | 12.3-16.1 (14.01) | 4.2-6.3 (5.60) | 6.7-9.8 (8.41) |
| 27 | 10 | 13.0-15.7 (14.28) | 4.9-6.2 (5.40) | 7.7-10.5 (8.88) |
| 28 | 13 | 13.9-20.9 (15.62) | 5.2-8.3 (5.75) | 8.5-12.6 (9.85) |
| 29 | 8 | 17.8-22.3 (19.79) | 6.3-8.4 (7.19) | 11.5-14.0 (12.60) |
| 30 | 9 | 20.3-24.8 (22.85) | 8.1-10.5 (9.32) | 10.5-15.5 (13.53) |
| 31 | 5 | 24.1-28.5 (26.61) | 9.4-11.2 (10.59) | 14.7-17.3 (16.02) |
| 34 | 5 | 24.8-29.4 (27.31) | 9.2-11.6 (10.73) | 15.6-18.5 (16.80) |
| 36 | 3 | 30.0-30.1 (30.07) | 10.1-12.2 (11.15) | 18.9-20.0 (19.44) |
| 37 | 4 | 28.9-34.1 (31.75) | 11.5-12.4 (11.88) | 17.4-22.5 (19.88) |
| 38 | 1 | 28.98 | 12.88 | 16.10 |
| 39 | 2 | 35.6-36.9 (36.25) | 14.00 | 21.6-22.9 (22.25) |
| 40 | 2 | 32.3-39.8 (36.05) | 14.00 | 18.3-21.8 (20.05) |
| 43 | 2 | 21.5-23.0 (22.25) | 14.2-14.8 (14.45) | 6.8-8.8 (7.80) |
| 44 | 4 | — | 14.5-15.6 (15.08) | — |
| 46 | 11 | — | 12.7-16.7 (14.26) | — |