The teeth of all species of Smilisca are spatulate and bifid. The numbers of maxillary, premaxillary, and vomerine teeth are summarized in Table 5. Smaller and presumably younger specimens of all species of Smilisca have fewer teeth than do larger specimens of the same species. This correlation between size and number of teeth does not exist as an interspecific trend within the genus; for example, the smallest species in the genus, S. puma, has the highest number of maxillary teeth. In small specimens of a given species wide gaps are present between the maxillary teeth posteriorly; in large specimens the gaps are filled by teeth, beginning anteriorly and progressing posteriorly, until the maxillary dentition is continuous.
No extensive study of the muscular system was undertaken, but certain muscles know to be of taxonomic importance were studied.
Jaw Musculature.—Starrett (1960) pointed out the unique jaw musculature in Smilisca. In this genus M. depressor mandibulae consists of two parts, one arising from the dorsal fascia and one from the posterior arm of the squamosal. Two muscles arise from the anterior arm of the squamosal and insert on the lateral face of the mandible. Of these muscles, M. adductor mandibulae posterior subexternus lies medial to the mandibular branch of the trigeminal nerve; the other, M. adductor mandibulae externus superficialis, lies lateral to the same nerve (Fig. 9). In most other hylids the latter muscle is absent. No significant variation in the position of the muscles was noted in the various species of Smilisca, though M. adductor mandibulae originate somewhat more anteriorly in S. baudini and S. cyanosticta than in the other members of the genus, all of which have a shorter anterior arm of the squamosal that does not reach the maxillary. The two separate parts of M. depressor mandibulae are not so widely separated in members of the sordida group as in the baudini group.
Fig. 9. Lateral view of the left jaw of Smilisca baudini; A. M. E. S., adductor mandibulae externus superficialis; A. M. P. S., adductor mandibulae posterior subexternus; Col., columella; D. M. depressor mandibulae; M. B. T. N., mandibular branch trigeminal nerve; Sq., squamosal. KU 64214, ×5.
