Natural History of Sceloporus Goldmani (Squamata: Phrynosomatidae) in Its Southern Distribution
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Herpetology Notes, volume 10: 161-167 (2017) (published online on 19 April 2017) Natural History of Sceloporus goldmani (Squamata: Phrynosomatidae) in its southern distribution Rubén Alonso Carbajal-Márquez1, 3,* and Gustavo Ernesto Quintero-Díaz2, 3 Introduction. frequency of appearance (FA) was calculated as the total frequency of a component, divided by the total number The bunchgrass lizard Sceloporus goldmani Smith, of scats. To consider the importance of all species, the 1937, belonging to the S. scalaris group, was believed percentage of occurrence (PA) was also calculated as the to be extinct due to habitat destruction, and surveys total frequency of a component, divided by the sum of with unsuccessful results in the historical localities in all frequencies (Aranda et al., 1995). The activities were the states of Coahuila, Nuevo León and San Luis Potosí, carried out under authorization of scientific collection for this reason have not been included in the most recent through document number SGPA / DGVS / 05143/14 analyses (Smith and Hall, 1974; Thomas and Dixon, and SGPA / DGVS / 030709/16. 1976; Sinervo et al., 2010; Bryson et al., 2012; Leaché et al., 2013; Grummer et al., 2014; Grummer and Bryson, Results. 2014). Recently new populations of this species were found in the states of Aguascalientes, Jalisco, San Luis Morphology. The specimens of Sceloporus goldmani Potosí and Zacatecas (Carbajal-Márquez and Quintero- reported here agree with the characters of Smith’s (1937) Díaz, 2016). Here we provide a brief description of original description. The specimens (N = 21; 10 males, these new specimens, as well as observations on their 11 females) measured on average 44.08 mm ± 11.15 mm natural history, which until now were poorly known. snout vent length (SVL), and the largest specimen was a female with 57.7 mm SVL; average total length (TL) Materials and methods. 83.27 mm ± 31.27 mm , and the largest TL was 111 mm in both sexes. They weighed on average 3.14 g ± 1.16 g; The counting of scales and morphological characters males weighed on average 3.41 g ± 0.69 g, and females were carried out based on the work of Smith (1937). The weighed 2.88 g ± 1.44 g. The average number of dorsal measurements were performed with a digital vernier scales was 52.62 ± 1.60, the average for ventral scales micrometric calibrator (resolution of ± 0.1 mm). The was 39.38 ± 4.42. They have 30-38 femoral pores in weight was obtained with a digital balance (resolution of series, separated by no more than two scales ± 0.1g). To determine diet, the scats were obtained from the specimens by palpation of the abdominal region Coloration. The coloration in life is as follows: the and analysed under a stereoscopic microscope. The background colour is grey or light brown; the top of the head generally has three to five dark brown spots, occasionally another five spots are present in the neck; in the dorsal region of the trunk there are thirteen to 1 El Colegio de la Frontera Sur. Departamento de Conservación fifteen pairs of dark brown or black crescent-shaped de la Biodiversidad. Unidad Chetumal. Av. Centenario Km marks bordered by white scales, and located between 5.5, 77014, Chetumal, Quintana Roo, México. a pair of clear lines that are cream or light yellow, 2 Universidad Autónoma de Aguascalientes, Centro de Ciencias ranging from the neck to the base of the tail. Below Básicas, Departamento de Biología, Avenida Universidad these lines, presents another series of equal number of No. 940, Aguascalientes, Ags. 20131, México. dark marks but smaller than those on the back. The tail E-mail: [email protected] has a series of six to twelve dark marks on the dorsum, 3 Conservación de la Biodiversidad del Centro de México, A. C. Andador Torre de Marfil No. 100, C. P. 20229, sometimes fused (Fig. 1, 2). The throat of the males is Aguascalientes, Aguascalientes, México. slightly barred with black marks, and in females this * Corresponding author e-mail: [email protected] barring is less perceptible; in the belly the males have 162 Rubén Alonso Carbajal-Márquez & Gustavo Ernesto Quintero-Díaz Figure 1. Male specimen of Sceloporus goldmani. Figure 2. Female specimen of Sceloporus goldmani. two pale blue abdominal marks (semeions) separated belly with some scattered black dots and they present by six to eight scales, and interrupted by black spots, reddish tones in the armpit when they are pregnant (Fig. and in reproductive season they present in the armpit an 4). Both sexes have a black spot on the shoulders, and orange dorsolateral patch that extends approximately to on the spot they have one to three blue scales that in the middle of the body (Fig. 3), the females have a white most cases are in the anterior region of that spot. In Natural History of Sceloporus goldmani in its southern distribution 163 Figure 3. Ventral view of a male specimen of Sceloporus goldmani. none of the specimens of the new populations was the Activity and behavior. They are diurnal lizards, having patternless phase observed. their activity in the morning and afternoon, and reducing Diet. Twenty one (21) scats belonging to 19 specimens their activity during the warmer hours of the day. They collected between February to June were analysed. Three prefer open sites where the vegetation is not very high, orders belonging to Hexapoda were found, the most and are usually found near shrubs, cactus (Opuntia) or important orders being Homoptera and Hymenoptera, rocks. A greater number of lizards were observed on as well as plant remains; (Table 1). the edges of the plateaus with slight inclination, areas with abundant rocks and scarce vegetation, and some Reproduction. On May 29, 2013 at 10:40 am, the mating behaviour was observed in the field, the male bit specimens were observed around anthills produced by the female’s tail and the female turned to bite the nape of the male forming a ring with their bodies, exposing the white belly that contrasted with the grass beneath, making them perhaps vulnerable to being depredated. Table 1. Diet pertaining to 21 scats of 19 specimens found 1 TABLE 1. Diet pertaining to 21 scats of 19 specimens found during this study (N = number of samples in which As we approached, they remained in that position for during this study (N = number of samples in which it at least five minutes, until the male 2released it appears, the female FA = Frequency appears, of appearance, FA = Frequency PA = Percentage of appearance, of appearance). PA = Percentage of and both tried to escape (Carbajal-Márquez et al., 2013). appearance). Neonates were observed on May 11,3 2014, as well as a pregnant female and a hatchling on June 13, 2013. ORDER N FA PA In order to verify if they were viviparous lizards, two Coleoptera 5 23.8 9.8 females were collected in February 2014, both gave Homoptera 21 100 41.1 birth to seven and eight offspring respectively on June Hymenoptera 19 90.4 37.2 11, 2014. The offspring are miniature replicas of adults Plant Remains 6 28.5 11.7 (Fig. 5). 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 164 Rubén Alonso Carbajal-Márquez & Gustavo Ernesto Quintero-Díaz Figure 4. Ventral view of female specimen of Sceloporus goldmani. Pogonomyrmex sp. When the lizards are discovered The coloration of S. goldmani is very similar to they undertake a race to hide under some creeping shrub other species in the S. scalaris group, highlighting the or cactus, or inside a burrow usually located under a presence of dark bars in the throat in both sexes, but rock, if there are no nearby shelters, they hide under the more evident in males. In addition the presence of pale grass, adopting a U- shaped position, or they try to go blue abdominal marks (semeions) interrupted by black unnoticed on the surface of the large, flat rocks, which spots in the males, and in females only the presence of they use as perfect camouflage. Some individuals were abdominal tenuous black spots (Smith, 1939). Another observed foraging, and at the moment of our approaching point of similarity with other species in the S. scalaris they undulated the tail parallel to the ground, perhaps as group is that males have an orange patch on the axilla an antipredator behaviour. Most of the specimens were that extends mid-body in breeding season. Additionally found with an approximate separation of 10 to 15 meters it is important to note the absence of a patternless between each of them. During our surveys the activity phase. was observed from middle February to November, with There are few published studies that address the more activity in the early rainy season. diet of species belonging to the S. scalaris group. The diet reported for S. brownorum in Aguascalientes Discussion. comprised the Hexapoda orders: Coleoptera, Diptera, Hymenoptera and Orthoptera; and Arachnida: Araneae Comparison with other members of the Scalaris (Vázquez-Díaz and Quintero-Díaz, 2005). Sceloporus group bicanthalis in the Tehuacán-Cuicatlán Valley feeds on The main differences of S. goldmani with the rest of the Hexapoda: Homoptera, Hemiptera, Coleoptera, the species of the S. scalaris group are the presence of Hymenoptera, and Arachnida: Araneae (Canseco- the lateral scales in definitely oblique rows, not parallel Márquez and Gutiérrez-Mayen, 2010). The diet of S. with respect to the dorsal; the number of dorsal scales slevini in Chihuahua consists of Hexapoda: Coleoptera, greater than 50; a short tail, and the viviparity . Due to Hemiptera, Hymenoptera and Orthoptera (Lemos- the obtained measurements of SVL and TL, S.