The Amphibians and Reptiles of Michoacan, Mexico Part 9

La Palma (8).

These specimens (USNM 113998-114005) are from the marshes along the southeastern sh.o.r.e of Lago de Chapala. Five females have snout-vent lengths of 124.0-138.1 (131.5), and one male has a snout-vent length of 110.2 mm. Two juveniles have snout-vent lengths of 49.7 and 56.3 mm. The coloration of the juveniles is more bold than that of the adults. The body proportions of these specimens agree with those presented by Zweifel (1957:80).

~Rana montezumae~ Baird

_Rana montezumae_ Baird, Proc. Acad. Nat. Sci. Philadelphia, 7:61, October 20, 1854.--Mexico City, Distrito Federal, Mexico.

La Palma; 8 km. NW of Maravatio (10); Sahuayo; Tupataro (7).

This species probably is more abundant and widespread than is indicated by the few specimens listed above. It has been found only in the vicinity of permanent water on the Mexican Plateau and the mountains rising from the plateau at elevations of 1500 to 2000 meters. Its apparent absence from Lago de Patzcuaro cannot be explained, unless _Rana dunni_ replaces it there.

~Rana pipiens~ Schreber

_Rana pipiens_ Schreber, Der Naturforscher, Halle, 18:185, 1782.--Racc.o.o.n, Gloucester County, New Jersey.

Aguililla (2); Apatzingan (13); Arteaga; Axolotl (16); Camachines (2); Capirio; Cascada Tzararacua (3); Cerro San Andres (6); Charapendo (4); Ciudad Hidalgo; Coalcoman (17); Cuitzeo (3); El Sabino (10); Jacona (3); 29 km. NW of Jacona (8); Jiquilpan; La Orilla (3); La Palma (5); La Playa (4); Lago de Chapala (3); Lago de Patzcuaro (6); Lombardia; Los Conejos (67); Los Reyes (7); Macho de Agua; Maravatio; Morelia (5); Opopeo (3); Patzcuaro (9); 26 km. S of Patzcuaro (52); Puerto Hondo (3); Rio Duero, 14 km. E of Zamora (13); Rio Tepalcatepec, 27 km. S of Apatzingan (2); San Gregorio (38); San Jose de la c.u.mbre (5); Tangamandapio; Zacapu; 18 km. W of Zamora (35).

Except on the Pacific lowlands, this species is abundant throughout the state. It has been collected from sea level to 2800 meters, the greatest alt.i.tudinal range of any amphibian in Michoacan. It has been found frequently in the Tepalcatepec Valley; it is not a distinctly highland species in southern Michoacan, as stated by Peters (1954:9). One specimen from Aguililla (UMMZ 119257) is an albino. In this specimen there is a faint pattern on the hind limbs; otherwise the entire body is creamy white; the eyes are pink.

~Rana pustulosa~ Boulenger

_Rana pustulosa_ Boulenger, Ann. Mag. Nat. Hist., ser. 5, 11:343, 1883.--Ventanas, Durango, Mexico.

Arteaga (4); 21 km. S of Arteaga; Cascada Tzararacua (3); Coalcoman (3); 12 km. ENE of Dos Aguas (3); El Sabino (53); Los Reyes (3); Tzitzio (4); Uruapan.

Although _Rana pustulosa_ seems to be absent from the Mexican Plateau in Michoacan, it has been collected at elevations of 850 to 2150 meters on the slopes of the Cordillera Volcanico and in the Sierra de Coalcoman.

Usually the frogs are found along rocky streams, but at Coalcoman they were found in a hyacinth-choked old river channel, and at El Sabino, in irrigation ditches.

In most specimens the dorsum is dark olive-brown; in some it is pale olive-tan with dense dark brown mottling on the back and dark transverse bands on the hind limbs.

Thirteen tadpoles (UMMZ 94271) taken from a seepage pool by a stream near Uruapan closely resemble the description of tadpoles of this species given by Taylor (1942b).

REPTILIA

Testudines

~Chelonia mydas~ (Linnaeus)

_Testudo mydas_ Linnaeus, Systema naturae, ed. 10:197, 1758.--Type locality restricted to Ascension Island by Mertens and Muller (1928:23).

_Chelonia mydas_, Brongniart, Bull. Sci. Soc. Philom., 2:89, 1800.

Beach between Rio Motin and Rio Colotlan (2); Maruata; Playa Azul (4).

Green sea turtles are abundant along the coast of Michoacan. Laying females and fresh nests were found on August 6-12, 1950, July 14-16, 1951, and July 8-10, 1955. The general account of sea turtles on the coast of Michoacan that was given by Peters (1957) is supplemented here by my field notes on the actions of one female observed on the night of July 14, 1951, near Maruata by Donald D. Brand and I. Because of a full moon, visibility was excellent.

In the course of the day several _Chelonia_ were seen in the surf; shortly after dark the first turtle was observed on the beach. Several were observed to come out on the beach and crawl nearly to the strand line, only to return to the sea.

At 10:20 p. m. one turtle was seen about 15 meters from the water. We watched this turtle from some distance and observed that by 10:26 p. m.

she had moved about ten meters to a bank of sand about two meters high.

Ten minutes later she had climbed the bank and disappeared over the top into the brush. We moved closer and remained hidden below the bank.

Although we could not see the turtle, we could hear her movements.

Between 10:37 and 10:57 p. m. the turtle dug, often flipping the dry sand for a distance of about two meters. When this energetic digging ceased, we moved up the bank to see that she was facing inland and sitting in a depression about one and one-half meters in diameter and 30 centimeters in depth. She had cleaned out this depression in the past 20 minutes. Between 11:00 and 11:36 p. m. she dug the nest hole by first scooping sand with one hind flipper and then with the other; when sand was thrown by one flipper, there was a similar, but weaker, motion by the other flipper. At 11:36 p. m. she stopped digging. By crawling up behind the turtle we were able to examine the nest cavity, which measured 21 centimeters across the top and 38 centimeters deep. The diameter of the bottom of the hole was estimated to be about 50 centimeters. At 11:40 p. m. she released the first egg; a minute later she dropped the second. At 11:42 p. m. the third and fourth eggs were released; these were coherent, as were the fifth and sixth eggs released at 11:43 p. m. After this, as many as three eggs were dropped at a time. After laying about 60 eggs, she paused for a minute and then continued laying. By 11:55 p. m. she had laid 98 eggs; after this, the process of deposition slowed considerably. She dropped a fragment of an egg followed by normal eggs. At midnight she deposited a miniature egg about 20 mm. in diameter. This terminated the deposition. Immediately she began to cover the nest.

Within ten minutes after the last egg was deposited the nest had been covered. The turtle first had been seen at 10:20 p. m.; judging from its speed and its distance from the water, the turtle probably had been on land for about ten minutes. About 25 minutes were used in crawling from the water to the nesting site. One hour and 33 minutes were spent at the nesting site; of this time twenty minutes were taken for egg deposition.

The turtle was not followed back to the water, but if the return trip took approximately the same amount of time as required to travel from the ocean to the nesting site, the total elapsed time from departure to return to the water was about two and one-half hours.

We collected the eggs as they were deposited. There were 106 eggs, each having a diameter of about 40 mm., plus one small egg and a fragment of another. The turtle had a carapace about one meter in length.

From our limited observations of sea turtles and their tracks on the beaches, and from the accounts of these animals by the residents of the coastal region, great numbers of sea turtles use these relatively uninhabited beaches for nesting grounds. However, the turtles do not go unmolested. The natives capture turtles and collect their eggs. Opened and emptied nests also showed signs of predatory activity on the part of other mammals. In the vicinity of Playa Azul several turtles were killed by dogs.

~Kinosternon hirtipes hirtipes~ Wagler

_Cinosternon hirtipes_ Wagler, Naturl. Syst. Amph., p. 37, 1830.--Mexico. Type locality restricted to Mazatlan, Sinaloa, Mexico, by Smith and Taylor (1950b:25).

_Kinosternon hirtipes hirtipes_, Schmidt, Check list N Amer.

Amph. Rept., ed. 6, p. 89, 1953.

Eight km. W of Ciudad Hidalgo; Jiquilpan; La Palma; Lago de Camecuaro (4); Lago de Cuitzeo (3); Lago de Patzcuaro (8); 14 km. E of Zamora (4).

One specimen from eight kilometers west of Ciudad Hidalgo (UIMNH 24707) is from the Rio Tuxpan, a tributary of the Rio Balsas; this is the only record for the species from the Balsas drainage. All others are from the lakes or rivers flowing into the lakes on the southern part of the Mexican Plateau. This species exists in Lago de Patzcuaro to the apparent exclusion of the abundant and widespread _Kinosternon integrum_.

~Kinosternon integrum~ LeConte

_Kinosternon integrum_ LeConte, Proc. Acad. Nat. Sci.

Philadelphia, 7:183, 1854.--Mexico. Type locality restricted to Acapulco, Guerrero, Mexico, by Smith and Taylor (1950b:25).

Agua Cerca (3); Aguililla; Arteaga (8); Apatzingan (7); Barranca de Herradero; Buenavista (20); Capirio (2); Charapendo (3); Chupio; Coahuayana (2); Coalcoman (169); Copuyo (4); El Sabino (8); Jacona; Jiquilpan (12); La Orilla (2); La Playa (2); Lago de Cuitzeo (27); Las Higuertas; Lombardia (3); Los Reyes (5); Morelia; Ojos de Agua de San Telmo; San Pedro Naranjestila; Tacicuaro.

Excepting Lago de Patzcuaro, _Kinosternon integrum_ occupies all permanent and temporary ponds, lakes, and streams below 2200 meters throughout the state. At Coalcoman the species was in roadside ditches, small puddles, flooded fields, a hyacinth-choked ox-bow of the Rio Coalcoman, as well as in the Rio Coalcoman and its tributaries.

Specimens from Arteaga and Barranca de Herradero were found in clear rocky streams; the one from Las Higuertas was found in a small muddy pond in pine-oak forest.

On August 26, 1960, James R. Dixon found a copulating pair in a pool at Capirio. The large series from Coalcoman contains juveniles and adults; these turtles formed the basis for the study of relative growth of plastral scutes in this species by Mosimann (1956).

~Geoemyda rubida perixantha~ Mosimann and Rabb

_Geoemyda rubida perixantha_ Mosimann and Rabb, Occ. Pap.