SPECIES OF QUESTIONABLE OCCURRENCE

Some species for which there are no authentic records from Michoacan can be expected there on zoogeographic probability. Other species have been recorded from Michoacan, but these records are doubtful for any one of several reasons. Fifteen species of such questionable occurrence are discussed below:

~Syrrhophus modestus modestus~ Taylor

_Syrrhophus modestus_ Taylor, Univ. Kansas Sci. Bull., 28:304, May 15, 1942.--Hacienda Paso del Rio, Colima, Mexico.

_Syrrhophus modestus modestus_, Duellman, Occ. Pap. Mus.

Zool. Univ. Michigan, 594:5, June 6, 1958.

This small terrestrial frog is not uncommon on the coastal lowlands and foothills in Nayarit and in Colima, where it has been collected within a few kilometers of the Michoacan border. At Tecolapa, Colima, on August 9, 1956, _Syrrhophus modestus modestus_ was found with _Tomodactylus nitidus orarius_, _Bufo marinus_, _Bufo marmoreus_, _Hyla baudini_, _Hyla smithi_, and _Phyllomedusa dacnicolor_, all of which occur on the coastal lowlands of Michoacan. Because of its solitary and secretive habits, _Syrrhophus modestus modestus_ is not common in collections.

Additional field work on the coast of Michoacan should reveal the presence of the species there.

~Hyla microcephala sartori~ Smith

_Hyla microcephala sartori_ Smith, Herpetologica, 7:186, December 31, 1951.--1 mi. N of Organos, S of El Triente, Guerrero, Mexico.

On August 28, 1960, J. R. Dixon obtained a series of this species from a temporary pond 6 kilometers northeast of La Resolana, Jalisco.

Previously, _Hyla microcephala sartori_ had been known only from the lowlands of Guerrero and Oaxaca. The existence of the species in Jalisco provides evidence that this frog also occurs in Michoacan and Colima.

~Gastrophryne usta usta~ (Cope)

_Engystoma ustum_ Cope, Proc. Acad. Nat. Sci. Philadelphia, 18:131, 1866.--Guadalajara, Jalisco, Mexico.

_Gastrophryne usta usta_, Carvalho, Occ. Pap. Mus. Zool.

Univ. Michigan, 555:13, July 16, 1954.

Smith and Taylor (1948:93-4) listed specimens of this species from Organos and El Treinta, Guerrero, and from Paso del Rio, Queseria, Santiago, and Tecoman, Colima. The species occurs from Sinaloa and central Veracruz southward at low elevations to the Isthmus of Tehuantepec and thence along the Pacific lowlands into Central America.

Almost certainly it occurs on the coastal lowlands in Michoacan. Since the amphibian fauna of the Tepalcatepec Valley has been better sampled than that of the coast, I suspect that if _Gastrophryne_ occurred in the Tepalcatepec Valley, I would have found it there.

~Lepidochelys olivacea~ (Eschscholtz)

_Chelonia olivacea_ Eschscholtz, Zool. Atlas, pt. 1, p. 2, 1829.--Manila Bay, Philippine Islands.

_Lepidochelys olivacea_, Girard, United States Exploring Expedition..., vol. 20, Herpetology, p. 435, 1858.

According to Smith and Taylor (1950b: 15), this sea turtle is known from the entire Pacific coast of Mexico; these authors reported the species from Chiapas, Oaxaca, Guerrero, Colima, and Sonora. Although the only sea turtle that I observed in Michoacan is _Chelonia mydas_, others probably do use the sheltered beaches for nesting. The scanty records of sea turtles along the Pacific coast of Mexico indicate that _Chelonia mydas_ and _Lepidochelys olivacea_ are the most abundant species in that region. There are scattered records of _Dermochelys coriacea_, _Caretta caretta_, and _Eretmochelys imbricata_ along the Pacific coast. The occurrence of any of these along the coast of Michoacan is probable.

~Geoemyda pulcherrima pulcherrima~ (Gray)

_Emys pulcherrima_ Gray, Catalogue of the Shield Reptiles in British Museum, vol. 1, p. 25.--Mexico. Type locality restricted to Presidio de Mazatlan, Sinaloa, Mexico, by Smith and Taylor (1950b:30).

_Geoemyda pulcherrima pulcherrima_, Wettstein, Sitzb. Akad.

Wiss. Wien, 143:18, 1934.

Smith and Taylor (1950b:30) recorded this species from Sonora, Sinaloa, Nayarit, Colima, and Guerrero; these records indicate that the species probably is distributed along the Pacific coast of Mexico southward from southern Sonora. It unquestionably occurs on the coast of Michoacan.

Natives of the coastal lowlands tell of another "tortuga de la tierra"

besides _Geoemyda rubida_. In the collections of the Museum of Natural History of the University of Illinois is a specimen of _Geoemyda pulcherrima_ from Mexcala in the Balsas Basin in northern Guerrero. On the basis of this specimen it is highly probable that the species also inhabits the Balsas-Tepalcatepec Basin in Michoacan.

~Pseudemys scripta ornata~ (Gray)

_Emys ornata_ Gray, Synopsis reptilium, p. 30, 1831.--Mazatlan, Sinaloa, Mexico.

_Pseudemys scripta ornata_, Carr, Herpetologica, 1:135, December 30, 1938.

The systematics and distribution of _Pseudemys scripta_ in Mexico and Central America are poorly understood. Smith and Taylor (1950b:32) recorded this turtle from the Pacific lowlands of Sinaloa, Jalisco, Oaxaca, and Chiapas. This species is represented by vicarious populations throughout the Atlantic lowlands of Mexico, northwestern Mexico, over much of the United States, and also in Baja California.

Along the Pacific coast of Mexico the species seems to be extremely rare, or, at least, only locally abundant. Since the species has such a wide distribution, and since it occurs on the Pacific lowlands both to the north and to the south of Michoacan, it is reasonable to expect its presence on the coast of Michoacan. Inquiries among the natives living in the Balsas-Tepalcatepec Basin produced only negative evidence about the occurrence of _Pseudemys_ in the Rio Tepalcatepec and Rio Balsas. I suspect that the best place to search for these turtles on the coast of Michoacan is in the numerous fresh-water lagoons on the coastal plain.

~Caiman crocodilus fuscus~ (Cope)

_Perosuchus fuscus_ Cope, Proc. Acad. Nat. Sci.

Philadelphia, 20:203, November 9, 1868.--Rio Magdalena, Columbia.

_Caiman crocodilus fuscus_, Mertens, Senckenbergiana, 26:275, December 22, 1943.

Gadow (1930:50) reported that _Caiman sclerops_ (= _Caiman crocodilus fuscus_) inhabited the "tierra caliente" in Michoacan. Smith and Taylor (1950b:212) accepted Gadow's record for the State, although otherwise the species is unknown north of Oaxaca. Peters (1954:10) refuted Gadow's record on the basis that Gadow's collections contained no specimens of _Caiman_. The local name "caiman" refers to both _Crocodylus_ and to _Caiman_, for, in general, the natives do not distinguish between the two. "Caimanes" are reported from along the coast of Michoacan, where the name presumably refers to _Crocodylus acutus acutus_, and in the Balsas-Tepalcatepec Basin (Gadow, 1930:50; Webber, 1946:267). I have seen no specimens of either _Crocodylus_ or _Caiman_ from the Balsas Basin. If crocodilians do occur in the basin, they probably are _Crocodylus acutus acutus_. There is no basis, whatsoever, for including Michoacan in the range of _Caiman crocodilus fuscus_.

~Bipes ca.n.a.liculatus~ Bonnaterre

_Bipes ca.n.a.liculatus_ Bonnaterre, Encyclopedie methodique, Erpetologie, p. 68, 1789.--Mexico. Type locality restricted to Mexcala, Guerrero, Mexico, by Smith and Taylor (1950b:39).

Duges (1896:480) reported this species from Morelia, Michoacan. Smith and Taylor (1950b:39), who recorded the species from three localities in the Balsas Basin in Guerrero, rejected Duges' record. I, too, am unwilling to accept Duges' record. Nevertheless, the species probably occurs throughout much of the Balsas Basin. This idea is strengthened by comments made by Storm (1939:342): "The last hard drop, that afternoon, was down the great Cerro de los Cajones [southwest of Tacambaro], and here in the upper forest we came upon... a lizard with front legs and none behind ... the animal with hands and no feet that senor Smith [Hobart M. Smith] was seeking!... They're named _Bipes caniculatus_ (_sic._)."

~Coleonyx elegans nemoralis~ Klauber

_Coleonyx elegans nemoralis_ Klauber, Trans. San Diego Soc.

Nat. Hist., 10:195, March 9, 1949.--Paso del Rio, Colima, Mexico.

Klauber (1945:199) and Smith and Taylor (1950b:43) reported this lizard from the coastal lowlands of Colima and Guerrero. Davis and Smith (1953:101) reported it from 8 kilometers northeast of Temilpa, Morelos, in the upper Balsas Basin. Specimens of this lizard have been collected infrequently; the few locality records and limited ecological data indicate that it inhabits dense scrub forest and tropical semi-deciduous forest. _Coleonyx elegans nemoralis_ is to be expected on the coastal lowlands, the seaward foothills of the Sierra de Coalcoman, and on the lower slopes of the Cordillera Volcanica along the northern edge of the Tepalcatepec Valley.

~Phrynosoma orbiculare orbiculare~ (Linnaeus)

_Lacerta obricularis_ Linnaeus, Systema naturae, ed. 12, 1:1062, 1789.--Mexico (by inference). Type locality restricted to Mexico, Districto Federal, by Smith and Taylor (1950b:97).

_Phrynosoma orbiculare orbiculare_, Smith, Trans. Kansas Acad. Sci., 37:290, 1934.