Body mottled brown and creamy gray above and below; mouth colored like body; caudal musculature creamy tan; caudal fin transparent; dark brown streak mid-laterally on anterior third of caudal musculature; rest of tail and all of caudal fin heavily flecked with brown; eye red in life.
Variation.—The third upper tooth-row is interrupted in all specimens; in some individuals the first upper and first lower rows are complete. The variation in size and proportions is given in [Table 2]. The dark brown lateral streak on the anterior part of the caudal musculature is distinct on most specimens; the only other variation in coloration is in the amount of brown flecking on the caudal musculature and fin.
Comparisons.—Ptychohyla schmidtorum schmidtorum differs from P. schmidtorum chamulae as stated in the diagnosis and in having pale creamy tan, as opposed to dark brown, webbing on the feet; and from P. ignicolor in having a depressed, as opposed to a flat, internarial region. Tadpoles of P. s. schmidtorum have a mottled appearance, as opposed to the more uniform brown color of P. s. chamulae.
Ptychohyla schmidtorum schmidtorum and several species of Plectrohyla are sympatric. All species of the latter genus have a bony prepollex, rugose skin on the dorsum, and heavy body; also sympatric is Ptychohyla e. euthysanota, which has a tarsal fold and in breeding males spinous nuptial tuberosities.
Life History.—This species breeds in clear mountain streams where males call from vegetation along the stream. The call consists of series of short notes, three to nine notes per series, sounding like "raa-raa-raa." The duration of each note is approximately .065 of a second, and has a rate of 96 to 119 pulses per second; the dominant frequency is about 3400 cycles per second. The call is almost indistinguishable from that of Ptychohyla schmidtorum chamulae.
Tadpoles and metamorphosing young were found at Finca La Paz, Guatemala, in late July, 1960. Two young lacking tails but not having completely developed mouths have snout-vent lengths of 14.2 and 14.6 mm. L. C. Stuart collected four metamorphosing young at Finca La Paz on May 6, 1949. By May 10 the frogs were completely metamorphosed, at which time they had snout-vent lengths of 15.5 to 17.0 (average 16.1) mm.
Remarks.—There is no doubt that this frog is most closely related to Ptychohyla schmidtorum chamulae, even though the ranges of the two subspecies are separated by the interior depression of Chiapas. Since at least at Finca La Paz, Guatemala, P. s. schmidtorum occurs with P. e. euthysanota, it is surprising that the former species has not been found at more localities along the Pacific slopes on northern Central America. At Finca La Paz in July, 1960, P. s. schmidtorum was more abundant than P. e. euthysanota.
Distribution.—This species is known only from a limited area at elevations between 1300 and 2200 meters on the Pacific slopes of the Sierra Madre in extreme eastern Chiapas and western Guatemala.
Specimens examined.—Mexico: Chiapas: Finca Irlandia, UMMZ 105429-30.
Guatemala: San Marcos: El Porvenir, CNHM 20755, 20761, 69904, UMMZ 80918; Finca La Paz, 2 km. W of La Reforma, KU 58016-44, 59940-2 (skeletons), 60050 (3 young), 60051 (tadpoles), 60052 (4 young), MCZ 34998-9, UMMZ 123144-7 (tadpoles).