Part 10

Oaxaca: Guichicovi (2); Matias Romero; 32 km. N of Matias Romero (2); Nueva Raza; Rio Sarabia (3); Santa Maria Chimalapa (14); Santiago Chivela; 12 km. S of Santiago Chivela (5); Santo Domingo (5); Tolosita (7). Veracruz: Acayucan (3); Alvarado; Amatitlan; Ayentes; Cosamaloapan (3); Cosoleacaque (6); Cuatotolapam (14); Hueyapan; 20 km. ENE of Jesus Carranza (6); 20 km. S of Jesus Carranza; 25 km. SE of Jesus Carranza (23); 35 km. SE of Jesus Carranza; 60 km. SW of Jesus Carranza (5); La Oaxaquena (4); Novillero (4); San Lorenzo (5).

Individuals were found in both wet and dry seasons. In the dry season they were most frequently found in rainforest, whereas in the rainy season breeding congregations were found in savannas as well. This toad occurs throughout the Gulf lowlands and on the Pacific slopes and in the Grijalva Valley of Chiapas and Guatemala, but not on the Pacific lowlands of the isthmus.

I have not been able to recognize individuals referrable to the race macrocristatus. Firschein and Smith (1957:219) described macrocristatus from the mountains of eastern Oaxaca and referred to it specimens from the Gulf lowlands of northern Chiapas. None of the present material shows the hypertrophied cranial crests supposedly characteristic of macroaristatus, nor do specimens from the isthmus resemble the population in the Grijalva Valley being described by L. C. Stuart, who will discuss the variation in, and the validity of, the named populations of valliceps.

Five specimens from San Lorenzo, Veracruz (USNM 123516-20), were identified as Bufo cristatus by Smith (1947:408). Firschein (1950:83) redefined the cristatus group of Bufo and assigned these specimens to valliceps.

=Eleutherodactylus alfredi= Boulenger

Oaxaca: Tolosita (2). Veracruz: 35 km. SE of Jesus Carranza (6).

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 Peten, Guatemala.

=Eleutherodactylus natator= Taylor

Veracruz: 35 km. SE of Jesus Carranza (3); 38 km. S of Jesus Carranza; 55 km. SE of Jesus 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 Camotlan, Oaxaca; northward in Veracruz the species inhabits foothills as far north as Huatusco.

=Eleutherodactylus rhodopis= Cope

Oaxaca: 30 km. N of Matias Romero; Rio Sarabia (5); Tapanatepec (87); Tolosita (6); between Zanatepec and Tapanatepec. Veracruz: 25 km. SE of Jesus Carranza; 35 km. SE of Jesus Carranza (2); 22 km. SSW of Jesus Carranza; 20 km. ENE of Jesus Carranza (7); Minatitlan; 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.

=Eleutherodactylus rugulosus= Cope

Oaxaca: La Princesa (30); Modelo; Santa Lucia (10); Tapanatepec (26); Tehuantepec (6); Tres Cruces (8). Veracruz: Tapalapan (5).

In addition to the specimens from the lowlands of the isthmus, for the purposes of the following discussion, I have included data on two specimens from the southern slopes of the Sierra del Sur in Oaxaca (Mirador and Chacalapa) and on several specimens from Los Tuxtlas in Veracruz (Los Chaneques, 67; Salto de Eyipantla, 35; and San Andres Tuxtla, 11).

Frogs of the Eleutherodactylus rugulosus complex occur from southern Veracruz and Sinaloa southward through Central America. Taylor (1940:401) described E. vocalis from Hacienda El Sabino, Michoacan; Taylor and Smith (1945:580) described E. avocalis from Tres Cruces, Oaxaca. These have been considered as species distinct from rugulosus, which is known to occur in Veracruz, Guerrero, and Chiapas southward into Central America. Although the large number of specimens collected in the isthmus does not aid in defining the ranges of the taxa involved, these specimens do give some idea of the variation in certain characters in a given population.

In specimens from Los Tuxtlas the tarsal fold is well-developed and extends two-thirds to three-fourths the length of the tarsus; the tibiotarsal articulation reaches the nostril and sometimes slightly beyond the tip of the snout. In males the tympanum is nearly equal to the diameter of the eye; in females it is about one-half the diameter of the eye. The posterior surfaces of the thighs are dark brown or black with whitish or cream-colored spots, flecks, or irregular mottling. The tarsal fold is dark; the throat is pale in some individuals, but in most is mottled with dark brown or gray flecks. Individuals from La Princesa near the continental divide in Oaxaca show the same variation in body proportions and development of the tarsal fold. The posterior surfaces of the thighs are dark brown indistinctly mottled with lighter brown. The throat is dark brown. Specimens from the Pacific slopes of Oaxaca, including the Plains of Tehuantepec, have dark brown thighs mottled with dusty cream. The tibiotarsal articulation extends slightly beyond the tip of the snout in all specimens. In males the tympanum is equal to about two-thirds the diameter of the eye. Duellman (1958b:6) discussed the variation in these characters in populations in Colima, Jalisco, and Michoacan.

Until the extent of variation of these characters is known throughout the range of rugulosus, the recognition of populations either as species or subspecies seems superfluous. Consequently, I have used the oldest name; this does not necessarily imply, however, that all populations of rugulosus (sensu lato) are conspecific.

Of the 200 specimens examined, 15 have a middorsal stripe that is red or yellow. The iris varies from a copper to a dark golden color and shines bright red at night. Many of the specimens are juveniles; these were collected in the dry season, at which time they were found beneath rocks along streams, in road culverts where there was some water, and in holes in banks and cliffs.

=Microbatrachylus pygmaeus= Taylor

Oaxaca: La Princesa (5); Matias Romero (9); Rio Sarabia (41); Tolosita (2). Veracruz: Jesus Carranza; 20 km. ENE of Jesus Carranza.

The specimens listed above vary widely in color patterns; some of the patterns are characteristic of certain named "species": albolabris, imitator, lineatissimus, and minimus. The large series from the Rio Sarabia contains all of the color patterns; this series was obtained in one small ravine in the rainforest. At least in the isthmian region, this species does not inhabit the Pacific slopes and lowlands.

=Syrrhophus leprus= Cope

Oaxaca: 33 km. N of Matias Romero; Santa Efigenia. Veracruz: San Lorenzo.