Smith (1942a:360) diagnosed _Sceloporus melanorhinus calligaster_ as having fewer femoral pores than the other subspecies of _S.
melanorhinus_ and as having the lateral belly patches in the males confluent in the midline. Examination of forty specimens from the Tepalcatepec Valley and the coastal regions of Michoacan does not substantiate this diagnosis. The number of femoral pores varies from 15 to 22 (18.9); 14 individuals (35%) had 20 or more femoral pores. Smith (_loc. cit._) stated that _S. melanorhinus_ in Oaxaca had 18 to 27 (21.6) femoral pores and that 77 per cent of the specimens had more than 20 femoral pores. Of the 24 males examined from Michoacan, 18 have the lateral belly patches separated in the midline. Usually they are separated by no more than one scale, but in some individuals they are separated by two or more scales. Although the above data minimize certain differences between the northern and southern populations of this species, certain of the color pattern characters seem to be diagnostic of the subspecies inhabiting the Pacific lowlands from Guerrero to Nayarit. Large adults of _S. m. calligaster_ have only a faint dorsal pattern, which in the subspecies _melanorhinus_ and _stuarti_ consists of a series of large, dark, interconnected triangles on the back. This pattern is present in young and small adults of _S. m.
calligaster_; furthermore, in this subspecies the ventral coloration of the males differs from that found in the more southern populations.
Adult males of _S. m. calligaster_ have a black throat, that changes to brilliant blue posteriorly, and a large white spot medially on the chin.
This spot is present in some specimens from Oaxaca and Chiapas, but, if present, it is much smaller and less distinct than in specimens from Michoacan. In _S. m. calligaster_ the chest and midventral area are orange to salmon-color.
A male from Lombardia in life was colored as follows: Dorsum grayish tan bearing faint bluish gray flecks; chest deep salmon-orange, this color continuing down midventral area to the somewhat paler groin; belly patches pale blue fading to pale green laterally; throat black anteriorly enclosing a white spot; throat blue posteriorly and bluish green posterolaterally.
Individual lizards were observed to change in dorsal color from a pale ashy gray to a rather dull brown. Normally, inactive individuals and those observed on overcast days were dull brown.
_Sceloporus melanorhinus calligaster_ is found in trees in riparian situations in the lowlands to elevations of about 1500 meters. It does not inhabit the arid tropical scrub forest in the Tepalcatepec Valley or on the coast, but in those areas is found in the gallery forests along streams and rivers. The lizards are wary and live high in the trees; they are especially difficult to locate in the rainy season, when the trees are in full leaf.
~Sceloporus pyrocephalus~ Cope
_Sceloporus pyrocephalus_ Cope, Proc. Acad. Nat. Sci.
Philadelphia, 16:177, September 30, 1864.--Colima, Colima, Mexico.
Acahuato (2); Apatzingan (142); Arteaga (4); 26 km. S of Arteaga (4); Capirio (6); Chinapa; Chupio; 19 km. S of Corralito (5); El Sabino (220); Jazmin (3); La Placita (8); La Playa (14); La Salada (6); Lombardia (5); Nueva Italia (14); Ojos de Agua de San Telmo (2); Oropeo (3); Ostula; Punta de San Telmo (3); Rio Cancita, 14 km. E of Apatzingan (13); Rio Marquez, 10 km. S of Lombardia (10); Rio Marquez, 13 km. SE of Nueva Italia (3); San Juan de Lima (2); Santa Ana (2); Tafetan (2); Tepalcatepec (2); Tzitzio (6); Volcan Jorullo (3).
This small species is extremely common in the Tepalcatepec Valley and noticeably less so on the coast. It is usually found on the ground in rocky areas, but males frequently have been seen on the trunks of low trees in the scrub forest. Alt.i.tudinally, it ranges from sea level to slightly more than 1000 meters. The s.e.xes are readily distinguished in the field (Oliver, 1937; Smith, 1939; Duellman, 1954b). In the dry season only males were observed in the Tepalcatepec Valley, but in the rainy season both s.e.xes were found in approximately the same numbers.
~Sceloporus scalaris scalaris~ Wiegmann
_Sceloporus scalaris_ Wiegmann, Isis von Oken, 21:370, 1828.--Mexico. Type locality restricted to Mexico, Distrito Federal, by Smith and Taylor (1950b:137).
_Sceloporus scalaris scalaris_, Smith, Occ. Pap. Mus. Zool.
Univ. Michigan, 361:2, December 15, 1937.
Carapan (2); Cheran; Ciudad Hidalgo; Huingo (3); Jacona (3); Jiquilpan (2); Lago de Camecuaro (2); Lago de Chapala; Lago de Cuitzeo (5); Morelia (4); Patzcuaro (4); Querendaro; Quiroga; Tacicuaro (5); Tarecuaro; Zacapu (4); Zamora (4); Zinapecuaro (11).
This small terrestrial species does not seem to be abundant anywhere in the state. It sometimes is found in open pine, oak, or pine-oak forest, but usually it is observed in areas supporting bunch gra.s.s. In such places the lizards sun and forage on the open ground and quickly take refuge in the large clumps of gra.s.s. Alt.i.tudinally, the species ranges from 1550 to 2300 meters. Although _Sceloporus scalaris scalaris_ has been found in a.s.sociation with _S. dugesi intermedius_, _S. spinosus_, and _S. torquatus_, it does not seem to form any close ecological a.s.sociation with any of these species. In the pine forests of the Cordillera Volcanica _S. s. scalaris_ is replaced by _Sceloporus aeneus aeneus_, another small terrestrial species that occurs in great abundance throughout the coniferous forests of the Cordillera Volcanica.
~Sceloporus siniferus siniferus~ Cope
_Sceloporus siniferus_ Cope, Proc. Amer. Philos. Soc., 11:159, 1869.--Pacific side of the Isthmus of Tehuantepec.
Type locality restricted to Tehuantepec, Oaxaca, Mexico, by Smith and Taylor (1950b:134).
_Sceloporus siniferus siniferus_, Smith and Taylor, Bull. U.
S. Natl. Mus., 199:134, October 26, 1950.
Twenty-six km. S of Arteaga; Barranca de Bejuco (2); Coahuayana; El Ticuiz (2); La Mira; La Orilla (2); La Placita (9); Maruata; Ojos de Agua de San Telmo; Ostula (4); Playa Azul (6); Pomaro (2); Puerto de las Higuerita; Santa Ana (3).
This small terrestrial species inhabits the dense arid tropical scrub forest on the coast and lower foothills of the Sierra de Coalcoman to elevations of about 150 meters. It also occurs in the lower Balsas Valley, but it has not been found in the scrub forest of the broad Tepalcatepec Valley. Perhaps the large number of _Sceloporus siniferus_ on the coastal lowlands is responsible for the small number there of _S.
pyrocephalus_, another terrestrial species of about the same size. The latter is abundant in the Tepalcatepec Valley, where _S. siniferus siniferus_ has not been found. _Sceloporus siniferus siniferus_ is a fast runner and difficult to collect; consequently, the small number of specimens available is not indicative of its abundance.
~Sceloporus spinosus spinosus~ Wiegmann
_Sceloporus spinosus_ Wiegmann, Isis von Oken, 21:370, 1828.--Mexico. Type locality restricted to Puebla, Puebla, Mexico, by Smith and Taylor (1950b:116).
_Sceloporus spinosus spinosus_, Martin del Campo, a.n.a.l.
Inst. Biol. Mexico, 8:262, 1937.
Cojumatlan (2); Huetamo Road; Lago de Cuitzeo (4); Maravatio (8); Tupataro (2).
Although this species is widespread on the southern part of the Mexican Plateau, it is uncommon in Michoacan. It has been collected only in rather open situations in the mesquite-gra.s.sland on the plateau between 1500 and 2300 meters, where it has been found in a.s.sociation with _Sceloporus dugesi intermedius_ and _S. scalaris scalaris_. Most specimens of _Sceloporus spinosus spinosus_ have been observed on rock fences. In this habitat the species is the larger member of a pair of species, the smaller of which is _Sceloporus dugesi intermedius_.
~Sceloporus torquatus torquatus~ Wiegmann
_Sceloporus torquatus_ Wiegmann, Isis von Oken, 21:369, 1828.--Mexico. Type locality restricted to Mexico, Distrito Federal, by Smith and Taylor (1950b:126).
_Sceloporus torquatus torquatus_, Cope, Proc. Amer. Philos.
Soc., 22:402, 1885.
Angahuan (31); Araparicuaro; Capacuaro (3); Carapan (11); Cerro Tancitaro; Cheran; Ciudad Hidalgo; Cojumatlan; Copandaro (2); Corupu (4); Cuseno Station (9); El alamo; Jacona (6); Jiquilpan (2); Jungapeo (3); Lago de Camecuaro; Lago de Chapala; Lago de Cuitzeo (3); La Palma (2); Los Conejos (3); Los Reyes (3); Maravatio (9); Morelia (17); Paracho (3); Patzcuaro (27); Pino Gordo; Querendaro (2); Quiroga; Sahuayo (3); San Jose de la c.u.mbre; San Juan de Panangaricutiro; Tacicuaro (10); Tancitaro (200); Tangamandapio; Tangancicuaro (3); Temazcal (2); Tupataro (5); Uruapan (136); Zacapu; Zinapecuaro (10); Zirimicuaro (12); Zitacuaro.
This large species inhabits the Mexican Plateau and the Cordillera Volcanica, but not the Sierra de Coalcoman, where apparently it is replaced by _Sceloporus bulleri_. _Sceloporus torquatus torquatus_ usually is found in pine or pine-fir forests at elevations between 1450 and 3000 meters. In many places it is almost entirely arboreal, but in areas where there are many fallen trees or rock fences and rock piles, many individuals have been found on the ground near the rocks or logs.
In the coniferous forests this species is a.s.sociated with _S. grammicus microtepidotus_ and _S. aeneus aeneus_.
The distinction made by Smith (1938:572) between the subspecies _S.
torquatus torquatus_ and _melanogaster_ is slight. Individuals with pale bluish spots are found throughout the range of the species in Michoacan; spotting is especially evident in the young. Individuals having an incomplete nuchal collar have been found at Maravatio and at Zinapecuaro in the northern part of the state; in this character these specimens resemble _S. torquatus melanogaster_, which is found to the north from Guanajuato to Zacatecas and San Luis Potosi.
~Sceloporus utiformis~ Cope
_Sceloporus utiformis_ Cope, Proc. Acad. Nat. Sci.
Philadelphia, 16:177, September 30, 1864.--Colima, Colima, Mexico.
Nineteen km. S of Arteaga (2); Cascada Tzararacua (17); Coahuayana (3); Coalcoman (6); El Sabino (2); El Ticuiz (2); Ostula (3); Pomaro; Rio Cachan; San Juan de Lima; Uruapan (26).
In Michoacan the range of this species is discontinuous. It has been found between 1050 and 1550 meters on the slopes of the Cordillera Volcanica, and on the coast and seaward slopes of the Sierra de Coalcoman up to an elevation of 900 meters. It is absent from the Tepalcatepec Valley. At Uruapan and at Cascada Tzararacua this lizard was found on the ground in oak forest or in open pine-oak forest; on the coast and foothills of the Sierra de Coalcoman it was found on the ground in the gallery forests along streams, and not in the scrub forest.
~Urosaurus bicarinatus tuberculatus~ (Schmidt)
_Uta tuberculata_ Schmidt, Amer. Mus. Novitates, 22:4, December 1, 1921.--Colima, Colima, Mexico.
_Urosaurus bicarinatus tuberculatus_, Mittleman, Bull. Mus.
Comp. Zool., 91:169, September, 1942.
Twenty-six km. S of Arteaga; Cascada Tzararacua (2); Chupio; Coahuayana; Coalcoman (8); El Sabino (2); Jungapeo; La Orilla (2); La Placita (4); Playa Azul (4); Pomaro (2); San Salvador (16);? Tupataro; Uruapan (12); Tzitzio; Zamora.
The known distribution and geographic variation of _Urosaurus bicarinatus_ in southwestern Mexico presents a confused picture. In general rugosity, specimens from the coastal region of Michoacan (Coahuayana, La Orilla, La Placita, Playa Azul, and Pomaro) resemble _U.
bicarinatus tuberculatus_ to the north along the Pacific coast.
Furthermore, specimens from the coast have less stippling in the gular region than do those from the Sierra de Coalcoman and the slopes of the Cordillera Volcanica. Specimens from the mountains have greatly carinate enlarged dorsals, large lateral tubercles, and heavily stippled throats; in these characters they resemble specimens from Morelos, Guerrero, and Oaxaca. As mentioned by Peters (1954:14), some specimens from La Orilla and San Salvador are like _U. bicarinatus bicarinatus_ in certain characters, and one specimen has the blue ventral patches restricted to the sternal area, a characteristic of _U. bicarinatus anonymorphus_ of Oaxaca and eastern Guerrero. Examination of all available specimens from Michoacan indicates that the nature of the dorsal scales is of little value in separating the subspecies. The specimens from Michoacan are here provisionally referred to _U. bicarinatus tuberculatus_, because cursory examination of specimens from several localities between Nayarit and Oaxaca shows that there are only minor differences between the named populations. Individuals from the northern part of the range are more rugose and have larger blue ventral patches and less gular stippling than those from the south.