One specimen of this large species was collected in 1951; it was found on a low branch in tropical semi-deciduous forest at an elevation of 65 meters. In life there were olive-gray blotches on a pale gray dorsum; the iris was a dark golden color. This species, which is known from only a few specimens, seems to be restricted to the coastal lowlands and low foothills from Guerrero northward to Nayarit. Shannon and Humphrey (1957) described _Phrynohyas corasterias_ from Nayarit. Their description was based on a small female having a snout-vent length of 34.4 mm. The new species was diagnosed as differing from _P. inflata_ in having less webbing on the feet, a poorly developed supratympanic fold, a more pustulate dorsum, and marked differences in dorsal pattern, color, and nature of antebrachial banding. The significance of the webbing was questioned by Shannon and Humphrey. The nature of the supratympanic fold and dorsal pustules changes with age (Duellman, 1956a:31). _Phrynohyas inflata_ is known to attain a snout-vent length of 95 mm. Dermal structures that undergo ontogenetic change are of little importance in comparing a juvenile with a large adult. The only significant difference in color pattern between _P. inflata_ and _P. corasterias_ is the presence of wide transverse bands on the limbs of the latter. In this respect _P. corasterias_ approaches _P. latifasciata_, a species known only from two specimens from southern Sinaloa. The acquisition of additional specimens from Jalisco, Nayarit, and Sinaloa may show that _P. inflata_ and _P. latifasciata_ are conspecific, as suggested by Duellman (1956a:21). Nonetheless, the specimen on which the description of _P. corasterias_ was based is not sufficiently different from the known specimens of _P. inflata_ to warrant specific recognition. ~Hyla arenicolor~ _Hyla arenicolor_ Cope, Jour. Acad. Nat. Sci. Philadelphia, ser. 2, 6:84, July, 1866.--Northern Sonora, México. Type locality restricted to Santa Rita Mountains, Pima County, Arizona, by Smith and Taylor (1950a:354). Agua Cerca; Cascada Tzararacua (3); Chinapa; Cojumatlán; Dos Aguas; El Sabino (25); El Espinal; Lago de Camécuaro; Lombardia (2); Tupátaro; Zinapécuaro.