These specimens were collected in rainforest. Shreve (1957:247) pointed out the close resemblance between E. alfredi and E. conspicuus from Piedras Negras, Guatemala, and treated them as subspecies. Examination of the specimens from the isthmus, together with seven from central Veracruz and one from Teapa, Tabasco, suggests an even closer relationship. Eleutherodactylus conspicuus was diagnosed by Taylor and Smith (1945:567) as differing from alfredi "in lacking a tarsal fold, in having shorter hind legs with the tibiotarsal articulation reaching only to the nostril instead of beyond the tip of the snout; the vomerine teeth barely reach the posterior level of the choanae." The specimen from Teapa has the vomerine teeth reaching to the posterior edge of the choanae; in the eight specimens from the isthmus the teeth reach the posterior edge of the choanae in two and to the middle of the choanae in six; in seven specimens from central Veracruz the teeth reach the posterior edge of the choanae in two and to the middle in five. The tibiotarsal articulation extends beyond the tip of the snout in the specimen from Teapa and in two from central Veracruz; in three specimens from the isthmus and in one from central Veracruz it extends only to the nostril; in the others it extends to the snout. The tarsal fold is absent in the specimen from Teapa, in three from the isthmus, and in all those from central Veracruz; it is weakly present in the others.
In the light of this evidence there seems to be little justification in recognizing two species or even two subspecies in this group. Consequently, Eleutherodactylus conspicuus Taylor and Smith (1945) is here placed in the synonymy of Eleutherodactylus alfredi Boulenger (1898), a species with a range extending from Cuautlapan and Potrero Viejo in central Veracruz southward and eastward in forested habitats to western El Petén, Guatemala.
Eleutherodactylus natator Taylor
Veracruz: 35 km. SE of Jesús Carranza (3); 38 km. S of Jesús Carranza; 55 km. SE of Jesús Carranza.
The snout-vent length is 42.0 mm. in a male and averages 59.5 mm. in three adult females. The tarsal fold is low and extends about half the length of the tarsus; the first and second fingers are subequal in length; the tibiotarsal articulation extends beyond the tip of the snout. The patches of vomerine teeth lie between the posterior margins of the choanae. The throat and belly are immaculate, and the soles of the feet are dark. In the isthmus this species can be distinguished from Eleutherodactylus rugulosus by less rugose skin on the dorsum and absence of dark ventral mottling.
The specimens reported here extend the known range of natator eastward from Camotlán, Oaxaca; northward in Veracruz the species inhabits foothills as far north as Huatusco.
Eleutherodactylus rhodopis Cope
Oaxaca: 30 km. N of Matías Romero; Río Sarabia (5); Tapanatepec (87); Tolosita (6); between Zanatepec and Tapanatepec. Veracruz: 25 km. SE of Jesús Carranza; 35 km. SE of Jesús Carranza (2); 22 km. SSW of Jesús Carranza; 20 km. ENE of Jesús Carranza (7); Minatitlán; Tapalapan (5).
For the purposes of the present study I am not recognizing Eleutherodactylus beati, E. dorsoconcolor, and E. venustus as specifically, or even subspecifically distinct from the earlier named E. rhodopis. Probably these are mere color varieties of a single species.
In the dry season frogs of this species were in humid forests, where they were most frequently found along small streams and in ravines. The species is widespread in the Gulf lowlands, but does not occur on the Plains of Tehuantepec. It does inhabit the Pacific slopes on the foothills of the Sierra Madre de Chiapas, the western part of which extends into eastern Oaxaca near Tapanatepec.