Summary

William Edward Duellman A Review of the Frogs of the Hyla bistincta Group

Breeding males of Hyla pachyderma have moderately large nuptial spines; the other species have small spines, except H. charadricola in which spines apparently are absent. A well-defined thoracic fold is present in H. pachyderma, and a weak fold is present in H. robertsorum; the other species lack folds. In all species there is an anal sheath; this sheath is longest in H. bistincta, in which the anal opening is directed ventrally at the level of the lower edge of the thighs.
Source: Gutenberg

William Edward Duellman A Review of the Frogs of the Hyla bistincta Group

Table 1.—Comparison of Certain Measurements and Proportions in the Species of the Hyla bistincta Group. (Data From Adult Males; Means Are Given in Parentheses Below the Ranges.)
Frogs in this group are rather drab in appearance. The dorsal color varies from dull green to various shades of brown. The most distinct aspect of the coloration is the different color patterns on the flanks and posterior surfaces of the thighs. The flanks in all species are marked with spots or reticulations.
Source: Gutenberg

William Edward Duellman A Review of the Frogs of the Hyla bistincta Group

The condition of the tarsal fold is characteristic of the species. The dispersion of dark pigment on the flanks is variable. The type of Hyla bistincta labeculata (USNM 123689) is extreme in the development of dark dashes on the flanks, but this condition is approached in several specimes from Oaxaca and Veracruz. For example, in some specimens from Cumbres de Acultzingo, Veracruz, the mottling on the flanks is bold; in others the flanks are reticulated.
Source: Gutenberg

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