Ctenosaura pectinata, Gray, Catalogue of the lizards... British Museum, p. 191, 1845.
Apatzingán (27); between Ario de Rosales and La Playa; Barranca de Bejuco; Capirio (2); Coalcomán (4); El Espinal; El Sabino (2); El Ticuiz; Jazmin (2); La Huacana; La Placita (8); La Playa (3); Limoncito; Lombardia; Motín del Oro; Playa Azul; Río Cancita, 12 km. E of Apatzingán (2); Río Marquez, 10 km. S of Lombardia (2);? Uruapan; Volcán Jorullo.
Ctenosaura pectinata is a common lowland species that ascends the slopes of the Sierra de Coalcomán and the Cordillera Volcánica to elevations of about 1050 meters (approximating the lower limits of the oak forest). The record from Uruapan (USNM 10234, collected by Dugès) is doubtful.
These large lizards are most easily observed on rock fences along roads. Near Apatzingán innumerable individuals can be seen in mid-morning. Later in the day, as the sun rises higher in the sky, the lizards retreat to the shade of the crevices in the fences. The abundance of these lizards in the Tepalcatepec Valley, together with evidence gathered from the natives of the valley, indicates that these lizards are seldom used for human consumption there. On the other hand, several people in Coalcomán consider the "iguana negra" (local name for Ctenosaura) to be a delicacy and serve it at every opportunity. In early July, 1951, brilliant green young of the year were collected at La Playa and at Coalcomán.
Enyaliosaurus clarki (Bailey)
Ctenosaura clarki Bailey, Proc. U. S. Natl. Mus., 73:44, September 26, 1928.—Ovopeo (= Oropeo), Michoacán, México.
Enyaliosaurus clarki, Duellman and Duellman, Occ. Pap. Mus. Zool. Univ. Michigan, 598:1, February 16, 1959.
Twelve km. SSW of Apatzingán; Capirio (7); Cofradía (3); El Espinal (2); 32 km. E of Huetamo; Jazmin (5); Oropeo (10); Rancho Nuevo; Río Cancita, 12 km. E of Apatzingán (8); Tepalcatepec (3); Zicuiran (6).
This species is known only from the low areas of the Balsas-Tepalcatepec Basin between elevations of 200 and 510 meters. It is commonly found in the open arid tropical scrub forest dominated by Prosopsis sp., Apoplanesia paniculata, and Cercidium plurifoliolatum. Continued collecting in the Tepalcatepec Valley has borne out the suggestions of Duellman and Duellman (1959) concerning the distribution and abundance of this lizard. Also, continued collecting in Colima and on the Pacific coast has failed to reveal the presence of Enyaliosaurus there.