Ptychohyla schmidtorum and P. ignicolor have slightly longer premaxillaries than the other species. The longer premaxillary is reflected in the larger number of teeth on the bone—9 to 11 (average 10) in four specimens of P. schmidtorum and 10 teeth in one P. ignicolor, as compared with 6 to 10 (average 7.9) in seven specimens of the other species. The number of maxillary teeth in the various species are: P. euthysanota euthysanota, 43; P. euthysanota macrotympanum, 38; P. leonhardschultzei, 38 and 40; P. spinipollex, 34 and 40; P. schmidtorum schmidtorum, 37 and 43; P. schmidtorum chamulae, 40 and 41; P. ignicolor, 43. The teeth on the premaxillary and anterior part of the maxillary are long, pointed, and terminally curved backwards. Posteriorly on the maxillary the teeth become progressively shorter and blunter.
Variation in number of vomerine teeth is shown in [Table 1].
Tadpoles
Tadpoles of the genus Ptychohyla are adapted to live in mountain streams. The bodies are streamlined, and the tails are long and have low fins (Figs. [4] and [5]). The mouths are large and directed ventrally. Tadpoles of the two groups of species have strikingly different mouthparts.
Fig. 4. Tadpoles of the Ptychohyla euthysanota group: (A) P. euthysanota euthysanota (KU 60042), (B) P. euthysanota macrotympanum (KU 60049), (C) P. leonhardschultzei (KU 68556), and (D) P. spinipollex (KU 60053). ×2½.