Notes on Some Lizards of the Genus Phrynosoma from Mexico

Abstract

2. A plateau group, consisting of cornutum and modestu!m, which, in Mexico, are confined to the northern part of the Mexican plateau west of the Sierra Madre Occidental, and north of about the 23d or 24th parallel. 3. A southern group, composed of boucardii, orbiculare (including cortezii and dugcsii), asio, taurus and braconnieri. This group is a heterogeneous composite which is somewhat puzzling, possibly due to incorrect data in certain cases. All species may be considered as inhabitants almost exclusively of the region south of about the 22d parallel. Orbiculare is an exception, for, although confined for the most part to the highlands on the edges of the plateau, within the areas of deciduous and pine forests, it extends also northward along the Sierra Madre Occidental at least as far as the city of Durango (Gunther, 1893), and possibly into Chihuahua (Terron, 1932). The records of orbiculare from the United States, of Hallowell (1853) and Holbrook (1838) were (fide Van Denburgh [1932]) based upon specimens of douglassii hernandesi and cornutum, respectively. Cope's (1900) record from Fort Huachuca was based, as one may gather from Stejneger's (1902) report on the reptiles of the Huachuca Mountains, upon a specimen of one of the above two species. Asio and braconnieri are typically inhabitants of semiarid basins of the southern part of the plateau. Asio also extends farther south, into Tehuantepec and Guatamala. Taurus may also be an inhabitant of the semiarid basins, as might be inferred from its habitus and from the meager available data. Giinther's (1893) record from Matamoros very probably infers the Matamoros of the state of Puebla, not of Tamaulipas. The same author also reports a specimen from Amula in Guerrero, at 8,000 feet. This latter is hardly consistent with other data on habitats, yet, until further knowledge of habitat preferences is available, the record cannot be refuted. Boucardii is possibly also characteristic of the high, western-central, semiarid plateau. Duges (1896) has recorded it definitely from Leon, Guanajuato. Six species and subspecies of Phrynosoma were collected by Doctor Taylor and myself in various states of Mexico during the summer of 1932. The following notes are based upon the specimens in this collection (to which catalogue numbers refer).