Ecology of Sceloporus undulatus speari (Sauria: Phrynosomatidae) from North-Central Chihuahua, México

Abstract

Studying populations of species with large geographic ranges can provide answers to questions regarding the relative roles of genetics and the environment in determining variation in ecological traits (e.g., life history, thermal physiology, demography). Perhaps no other species of lizard has received as much attention in this regard as Sceloporus undulatus, which has been the subject of numerous statistical and theoretical analyses of geographic variation in life-history traits (e.g., Tinkle and Ballinger, 1972;Tinkle and Dunham, 1986;Gillis and Ballinger, 1992; Adolph and Porter, 1993, 1996;Niewiarowski, 1994;Smith et al., 1996). More recently, populations of S. undulatus have been the focus of more experimental investigations into the causes of such geographic variation (e.g., Ferguson and Talent, 1993;Niewiarowski and Roosenburg, 1993;Niewiarowski, 1995Niewiarowski, , 2001 Angilletta, 2001a,b).Although S. undulatus has served as a model organism for studying geographic variation, much of the information used in these analyses has come from North American populations and subspecies. Relatively little detailed information is known about the biology and ecology of the Mexican populations and subspecies of S. undulatus (but for studies on Sceloporus belli, formerly Sceloporus undulatus belli in Durango, México, see Barbault et al., 1978;Barbault and Maury, 1981; Gadsden-Esparza and Aquirre-León, 1993). We studied a population of Sceloporus undulatus speari from the Transmontane sand dune region of northern Chihuahua, México. Our objective was to provide additional information on the understudied populations and subspecies of S. undulatus in México so that future synthetic studies of S. undulatus ecology have greater geographic representation. MATERIALS AND METHODSOur study site was located at the Rancho El Setenta, Municipio Juárez (31°13′34.9″N, 106°30′29.7″W; 1282 m elevation) in northern Chihuahua, México. The study area lies within the transmontane sand dunes area located on the windward sides (south and west) of the Samalayuca, El Presidio, and associated mountain ranges. At our study site, the sand dunes are semistabilized with numerous fence posts and yucca (Yucca fi lifera).Lizards were collected by hand or by using rubber bands in July and August of 1998 and 1999. We recorded the microhabitat and the amount of sunlight (e.g., sunny vs. shaded) where the lizard was fi rst seen. Upon capture, we measured body temperature (T b ) to nearest 0.1°C using a quick-reading cloacal thermometer. We measured snout-vent length (SVL) to the nearest 1 mm using a plastic ruler.Lizards were collected by hand and preserved shortly after collection (initially in 10% formalin, and fi nally in 70% ethanol; deposited in the herpetological collection of the Laboratorio de Ecología of the Unidad de Biología, Tecnología y Prototipos). Measurements were then made on each individual including SVL, maximum head width (HW) and head length (HL; from anterior edge of ear to tip of snout). Snout-vent length was measured to the nearest...

Comparación de la dieta de tres especies simpátridas de Sceloporus en el valle semiárido de Zapotitlán, Mexico

“…Relatively little detailed information is known about the biology and ecology of many lizards in Mexico (Lemos-Espinal et al, 2003), especially from the tropical dry forest regions. Thus, conclusions regarding the ecology and life history characteristics of lizards from such habitats will not be known until considerably more data become available.…”

Ecologia térmica do lagarto Sceloporus gadoviae (Squamata: Phrynosomatidae) em uma região semi-árida do sul de Puebla, México.

“…In contrast, Lemos-Espinal et al (1997a) did not find a significant difference in T b between males and females, but did find significant differences in the environmental temperatures at the site of capture of males and females. Within Sceloporus, males with higher mean T b s than in females have been reported for S. scalaris and S .mucronatus (Lemos-Espinal et al 1997b, Smith et al 1993, with lower mean T b in S. undulatus erythrocheilus (Gillis 1991) and no difference in mean T b between males and females in a number of other species (e.g., Vial 1984, Guyer and Linder 1985, Lemos-Espinal and Ballinger 1995, LemosEspinal et al 1997c, 2001, 2003. Possible explanations for the differences in mean T b between and within sexes may include habitat partitioning for basking, activity at different times, or behavior.…”

Synopsis and taxonomic revision of three genera in the snake tribe Sonorini

“…This species is in the subgenus Procinura along with Sonora mosaueri. It is worth noting that while the name Procinura has historically been applied to Sonora aemula, this name was only briefly in use after synonymy with Sonora in 1945 (Bogert and Oliver 1945) from 1945-1955(Smith and Taylor 1945Maldonado-Koerdell 1953;Zweifel and Norris 1955) and from 2004(Lemos-Espinal et al 2004a, 2004b, 2004cSmith et al 2006;Cox et al 2012).…”