_Cnemidophorus deppei deppei_, Cope, Trans. Amer. Philos.

Soc., 17:31, 1892.

Salitre de Estopila; San Pedro Naranjestila.

This small species, which is extremely abundant on the coastal lowlands of Guerrero, seems to be rare on the coast of Michoacan, where it has been taken at elevations of 130 and 500 meters in open situations in otherwise forested areas. Duellman and Wellman (1960:25) discussed these specimens in relation to their subspecific a.s.signment. They were referred to _Cnemidophorus deppei lineatissimus_ by Peters (1954:18).

~Cnemidophorus deppei infernalis~ Duellman and Wellman

_Cnemidophorus deppei infernalis_ Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:32, February 10, 1960.--Mexcala, Guerrero, Mexico.

Acahuato; Apatzingan (227); Capirio (3); El Sabino; Jazmin; La Playa (6); Lombardia (6); Nueva Italia (4); Rio Marquez, 10 km. S of Lombardia (6); Rio Marquez, 13 km. SE of Nueva Italia (10); south of Tancitaro; Volcan Jorullo (3).

This is one of the most abundant and widespread lizards in the Tepalcatepec Valley. Throughout its range it is ecologically a.s.sociated with _Cnemidophorus costatus zweifeli_, which ranges to elevations somewhat higher than the 1050 meters known for _C. deppei infernalis_.

This small lizard reaches its greatest abundance in gra.s.sy areas on the floor of the Tepalcatepec Valley, where in the _Cercidium-Prosopis-Apoplanesia_ a.s.sociations it occurs with _Cnemidophorus calidipes_.

Duellman and Wellman (1960) discussed the variation and relationships of _Cnemidophorus deppei_, of which the subspecies _infernalis_ is restricted to the Balsas-Tepalcatepec Basin.

~Cnemidophorus lineatissimus exoristus~ Duellman and Wellman

_Cnemidophorus lineatissimus exoristus_ Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:44, February 10, 1960.--Rancho Santa Ana, four kilometers northeast of San Salvador, Michoacan, Mexico.

Thirteen to 25 km. S of Arteaga (18); Capirio (19); Limoncito (13); Santa Ana (22).

As in _Cnemidophorus calidipes_, the distribution of this subspecies seems to be restricted to the Tepalcatepec Valley, except in the vicinity of Arteaga, where it occurs on the southern slope of the Sierra de Coalcoman. As pointed out by Duellman and Wellman (1960:46), the specimens from south of Arteaga are like those from the Tepalcatepec Valley in scutellation and coloration, and not like _Cnemidophorus lineatissimus lividus_ from the geographically closer coastal lowlands.

In the Tepalcatepec Valley _Cnemidophorus lineatissimus exoristus_ inhabits gallery forests along the larger streams; in this habitat it is a.s.sociated with _Ameiva undulata sinistra_. From the other species of _Cnemidophorus_ in Michoacan, _C. lineatissimus exoristus_ can be distinguished by the possession of seven longitudinal stripes in adults and by the characters of scutellation given in Table 5.

~Cnemidophorus lineatissimus lineatissimus~ Cope

_Cnemidophorus lineatissimus_ Cope, Proc. Amer. Philos.

Soc., 17:94, 1877.--Colima and Guadalajara. Type locality restricted to Colima, Colima, Mexico, by Smith and Taylor (1950b:179).

_Cnemidophorus lineatissimus lineatissimus_, Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:41, February 10, 1960.

Boca de Apiza (4).

These specimens have 117 to 126 dorsal granules at midbody, a noticeably lower count than that for _Cnemidophorus lineatissimus lividus_ on the coast of Michoacan, which has 126 to 164 (148). Apparently these specimens represent immature _C. lineatissimus lineatissimus_; the differences between these and _C. lineatissimus lividus_ from nearby localities indicate that possibly the populations are distinct species and not subspecies, as suggested by Duellman and Wellman (1960:41).

~Cnemidophorus lineatissimus lividus~ Duellman and Wellman

_Cnemidophorus lineatissimus lividus_ Duellman and Wellman, Misc. Publ. Mus. Zool. Univ. Michigan, 111:50, February 10, 1960.--Maruata, Michoacan, Mexico.

Barranca de Bejuco (4); Boca de Apiza (2); Coahuayana (6); El Ticuiz (7); La Placita (11); Maruata (7); Motin del Oro; Ostula (5); Playa Azul (4); Playa Cuilala (2); Pomaro (2); Salitre de Estopila (2); San Pedro Naranjestila.

This is the most abundant and widespread species of _Cnemidophorus_ on the coastal lowlands of Michoacan, where it ranges from sea level to elevations of about 500 meters. In this area it inhabits dense arid scrub forest and semi-deciduous broad-leafed forest. Both of these habitats are continuous, or nearly so, along the lowlands and foothills of the Sierra de Coalcoman. This in itself may explain the abundance of _Cnemidophorus lineatissimus_ and the relative scarcity of _C. deppei_ and _C. communis_ in the coastal area, for _C. deppei_ and _C. communis_ usually inhabit more open arid scrub forest, as occurs in the Tepalcatepec Valley. Living in the dense scrub forest with _C.

lineatissimus_ is _Ameiva undulata sinistra_.

~Cnemidophorus scalaris~ Cope

_Cnemidophorus gularis scalaris_ Cope, Trans. Amer. Philos.

Soc., 17:47, 1892.--Chihuahua, Chihuahua, Mexico.

_Cnemidophorus scalaris_, Zweifel, Bull. American Mus. Nat.

Hist., 117:72, 1959.

Araro (2); Jacona; Lago de Cuitzeo (42); Morelia; 21 km. N of Morelia (4).

Zweifel (1959a:72) a.s.signed the small species of _Cnemidophorus_ having a relatively low number of dorsal granules and inhabiting the southern part of the Mexican Plateau to _C. scalaris_, which he diagnosed as rarely exceeding 100 mm. in snout-vent length and always having an average of less than 100 dorsal granules at midbody and usually less than 90. Forty-two specimens from the south sh.o.r.e of Lago de Cuitzeo (UMMZ 119558) have 80-91 (85.8) dorsal granules. Four specimens from 21 kilometers north of Norelia (UIMNH 6952 and UMMZ 104743) have 89, 78, 92, and 84 granules; one from Morelia (UMMZ 104742) has 78; two from Araro (UMMZ 119522) have 80 and 87; one from Jacona (UIMNH 24703) has 88.

Since no large adult males are present in the series from Michoacan, an adequate comparison of coloration between these and populations on the northern part of the Mexican Plateau cannot be made. _Cnemidophorus scalaris_ is a name applied to the lizards inhabiting the Mexican Plateau from Chihuahua south to Puebla by Zweifel (1959a:72). It is doubtful if all of the populations a.s.signed to this subspecies belong there; possibly more than one species is involved, but the paucity of material prevents further a.n.a.lysis at this time.

~Heloderma horridum horridum~ (Wiegmann)

_Trachyderma horridum_ Wiegmann, Isis von Oken, 22:421, 1829.--Mexico. Type locality restricted to Huajintlan, Guerrero, Mexico, by Smith and Taylor (1950b:193).

_Heloderma horridum horridum_, Bogert and Martin del Campo, Bull. Amer. Mus. Nat. Hist., 109:20, April 16, 1956.

Apatzingan; Coalcoman; La Placita; Oropeo; Paracuaro.

This species is known from elevations of less than 1000 meters in the Tepalcatepec Valley, the Sierra de Coalcoman, and the coastal lowlands.

Specimens from Coalcoman, La Placita, and Paracuaro came from areas of dense woods; those from Apatzingan and Oropeo might have come from patches of dense woods in the otherwise open scrub forest of the Tepalcatepec Valley.

~Gerrhonotus imbricatus imbricatus~ Wiegmann

_Gerrhonotus imbricatus_ Wiegmann, Isis von Oken, 21:379, 1828.--Mexico. Type locality restricted to Mexico, Distrito Federal, by Smith and Taylor (1950b:201).

_Gerrhonotus imbricatus imbricatus_, Dunn, Proc. Acad. Nat.

Sci. Philadelphia, 88:475, October 20, 1936.

Acuaro de las Lleguas (9); Cerro Barolosa (4); Cerro Tancitaro (36); Dos Aguas (22); Paracho; Sierra Patamba; Tinguidin; Zacapu.

Specimens from the Sierra de Coalcoman are noticeably different from those inhabiting the mountains rising from the Mexican Plateau. Of 45 specimens from Cerro Tancitaro and adjacent areas on the Mexican Plateau and in the Cordillera Volcanica, 15 have twelve longitudinal rows of dorsal scales and 30 have fourteen rows. Of seven specimens from the state of Mexico, 5 have twelve rows and 2 have fourteen; of nine specimens from central Veracruz, 8 have twelve rows and one has fourteen; of six specimens from Hidalgo, 5 have twelve rows and one has sixteen; of two specimens from Guanajuata, one has fourteen and the other has sixteen rows. All of the 35 specimens from the Sierra de Coalcoman have sixteen rows. Furthermore, these specimens have the superciliary row extended anteriorly, so that the anterior superciliary is in broad contact with the loreal. Specimens from Cerro Tancitaro have a shorter superciliary row, so that the anterior superciliary is not in broad contact with the loreal. These characters were used by Tihen (1949:220) to distinguish _Gerrhonotus imbricatus ciliaris_ from _G.

imbricatus imbricatus_. According to Tihen, the subspecies _G.

imbricatus ciliaris_ ranges from Guanajuato and Hidalgo northward to Chihuahua and Coahuila, whereas the nominal subspecies occurs from Michoacan and Hidalgo southward to Oaxaca. Specimens from the Sierra de Autlan in Jalisco are like those from Cerro Tancitaro; consequently, there seems to be no connection between the populations of _G.

imbricatus ciliaris_ in the mountains of the northern part of the Mexican Plateau with the _ciliaris_-like individuals found in the Sierra de Coalcoman. The acquisition and study of additional material from throughout the range of the species is necessary to clarify the picture of geographic variation. Until then, I prefer to consider all of the specimens from Michoacan as _Gerrhonotus imbricatus imbricatus_.

The largest specimen is a male having a snout-vent length of 136 mm. Two juveniles collected in July 24, 1960, have snout-vent lengths of 36 and 42 mm. A specimen having a snout-vent length of 127 mm. and a tail length of 145 mm. was regurgitated by a _Crotalus pusillus_, which had a body length of 550 mm.

_Gerrhonotus imbricatus imbricatus_ is an inhabitant of coniferous forests. In the Cordillera Volcanica it occurs from 1500 to 3500 meters at the top of Cerro Tancitaro. In the Sierra de Coalcoman it occurs from 2100 to 2700 meters. On July 4, 1955, a pair was found in copulation beneath a pine log at 2700 meters on Cerro Barolosa. The male was lying on top of the female and was holding her head firmly in his jaws; the male's tail was curled under the female's tail, so that the cloacae were in contact.

Serpentes