Zoobooks 4(10):1-20. _ _. 1992. Zoobooks: snakes. Wildlife Education, San Diego. 20 pp. WRIGill, 1. 1878. A very wonderful freak of nature. Mining and Science.
individuals of a distinct race, but universallionsters. Amer. J. Sci. Linhares municipality, Espirito Santo, southeastern Brazil. The 10:48-53. elevation in the reserve varies between 30 and 60 m. The climate ROSSMAN, D. A, AND G. R. STEWART. 1987. Taxonomic reevaluation of is wet and warm, with annual rainfall of 1300 mm and mean an Thamnophis couchii (Serpentes: Co1ubridae). Occ. Pap. Mus. Zool. nual temperature of 23°C (Jesus 1988). This study was conducted Louisiana State Univ. (63): 1-25. in July 1993, during the dry season. ScHMIDT, K. P., ANDR. F.lNGER. 1957. Living reptiles ofthe world. Nanover Metho~.-We made observations in the field from 0630 to 1800 House, Garden City. 287 pp. h. Lizards were collected in the course of 13 days using five pit SHAW, C. E. 1955. Dudley's second birthday. Zoonooz 28(12):11. fall traps provided with 10 m drift fences. We visited the pitfalls _ _. 1956. Dudley Duplex did it again! Zoonooz 29(12):12. regularly (at half-hour intervals) and checked for the presence of _ _. 1958. Dudley Dup1ex... devours two mice at the same time. lizards. In addition, we walked along a trail in the restinga look Zoonooz 31(11):9. _ _. 1959. Double trouble. Zoonooz 32(11):10-11. • ing for lizards. When a lizard was sighted the hour of activity was _ _. 1968. Double trouble again. Zoonooz 41(4):4-6. recorded and an attempt was made to capture it by hand. When _ _. 1971. A two-headed tale. Zoonooz 44(3):4-7. ever we failed such an attempt and the lizard moved to the inte _ _,ANDS. CAMPBELL. 1974. Snakes of the American West. AlfredA rior of a thicket of grass, we rapidly established a pitfall trap with Knopf, New York. 332 pp. fences near the thicket. Then, we kicked at the grass thickets to SMITH, H. M., AND G. PEREZ-HIGAREDA. 1988. The literature on startle the lizard and drove it to the pitfall trap. We also some somatodichotomy in snakes. Bull. Maryland Herpetol. Soc. (1987) times used a rifle to improve lizard collecting. Each lizard's cloa 23: 139-153. cal temperature was recorded (to the nearest 0.2°C) using a SNIDER, A T., AND J. K. BOWLER. 1992. Longevity of reptiles and am Schultheis quick-reading cloacal thermometer. For thermal biol phibians in North American collections. 2nd ed. SSAR Herpetol. Circ. (1):1-40. ogy purposes we only considered those lizards collected by rifle STRECKER, 1. K., JR. 1926. Ophidian freaks. Two-headed snakes. Contrib. or those dislodged from grass tufts and driven to the pitfalls, if Baylor Univ. Mus. (6):10. temperature measurement was made within 30 s from the first WEXo,1. B. 1981a. Snakes. Wildlife Education, San Diego. 20 pp. observation. The temperatures of the air (1 cm above ground) and _ _. 1981b. Zoobooks: Las serpientes. Wildlife Education, San Di substrate where each lizard was first sighted were also recorded. ego.20pp. For lizards found inside the pitfalls, temperatures were not con _ _.1987. Snakes. Zoobooks 4(10):1-20. sidered. The hour at which each lizard was active at the time of its _ _. 1992. Zoobooks: snakes. Wildlife Education, San Diego. 20 pp. first sighting was also recorded. The mean activity temperature WRIGill, 1. 1878. A very wonderful freak of nature. Mining and Science of M. agilis was estimated as the mean average of the body tem Press, Feb. 16,36(7).
V.WALLACH 4 Potter Park
Cambridge, Massachusetts 02138, USA.
Ecological Observations of the
Scincid Lizard Mabuya agilis in a
Brazilian Restinga Habitat
Scincid lizards of the genus Mabuya are common in tropical regions and widespread in South America. About twelve species of this genus (out of 85) are found in Brazil (peters and Donoso Barros 1970), occurring in all Brazilian ecosystems. Relatively few ecological studies have been conducted for Brazilian species of Mabuya (e.g., Rebou\(as-Spieker 1974; V~o]ini and Rebou\(as-Spieker 1973,1976; Vitt 1991; VittandBlackbum 1991; Vrcibradic and Rocha, ms. submitted); hence, their ecology is in general, poorly known. Mabuya agilis is a small lizard (60-70 mm SVL) that inhabits open coastal habitats common in southeastern Brazil (Araujo 1984; Vrcibradic and Rocha, ms. submitted). In Linhares, southeastern Brazil (see below), M. agilis inhabits "restinga" habitats, occur ring in grass tufts or near the base of shrubs and bromeliads (pers. obs.). Restingas are coastal Quaternary sand dune habitats cov ered with sparse herbaceous and shrubby vegetation (Suguio and Tessler 1984). In spite of its relative abundance in the area, this species has relatively reclusive habits, compared to sympatric liz ard species (e.g., Tropidurus torquatus, Cnemidophorus ocellifer, Ameiva ameiva) (Bergallo and Rocha 1993, 1994). Study Area.-ln this study, we present data on food habits, ther mal biology and activity of Mabuya agilis in Linhares. Field work was carried out in a "restinga" habitat (locally called "Nativo") in the Reserva Florestal Vale do Rio Doce (l9°18'S, 400 19'W),
peratures of active lizards (Brattstrom 1965). Variation in body temperature throughout the day was estimated by averaging the body temperatures within each hour interval. Air and substrate temperatures within each hour interval were also averaged for comparisons with the lizards' daily variation in body tempera ture. The relationship between body temperature and air and sub strate temperatures, respectively, were analyzed by regression analyses and multiple regression (Zar 1974). The stomach contents of 18 M. agilis were analyzed and iden tified to order. For each lizard we counted the number of prey of each type and each item was measured with a Vernier caliper (to the nearest 0.1 mm) and its volume (in rpm3) was estimated by multiplying its three dimensions (length, width, and depth; Schoener 1967). Diet composition was then described in terms of number and volume of each prey type in the sample, and of fre quency, defmed as the number oflizard stomachs containing each prey type. Activity.--Mabuya agilis was active between 0800 and 1700 h and had a unimodal activity pattern, with a peak between 0900 and 1100 h (Fig. 1). This activity pattern (including peak and ex tension) is similar to that of other species of this genus in differ entareasofBrnzil(Vitt 1991; VittandBlackburn 1991; Vrcibradic and Rocha, ms. submitted). An extensive activity period for liz ards of the genus Mabuya has also been demonstrated to occur in other continents (e.g., Huey and Pianka 1977). Thermal Biology.-Body temperatures of M. agilis ranged from 25.O"C to 36.4°C with a mean activity temperature of 31.4 ± 3.1 SD (N = 24). Highest body temperatures were recorded between 1400 and 1500 h (mean = 34.5 ± 1.8 SD, N = 2) and the lowest between 1600 and 1700 h (mean =25.8 ± 1.1 SD, N =2)(Fig. 2), when the lizards retreat to shelter. The decline of the mean tem peratures (air, substrate, and body) observed between 1200 and 1300 is due to cloud cover during that time period on both days on which those particular data were obtained. Body temperature was significantly cOITelated to both air temperature (r = 0.90, P
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LITERATURE CITED ANDERSON, R. A. 1993. An analysis of foraging in the lizard Cnemidophorus tigris. In J. W. Wright and L. J. Vitt (eds.). Biology of Whiptail Lizards (Genus Cnemidophorus), pp. 83-116. Oklahoma Mus. Nat. Hist., Norman. ARAuJO, A F. B. 1984. Padr5es de divisao de recursos em uma comunidade de lagartos de restinga. In L. D. de Lacerda, D. S. D. Araujo, R. Cerqueira e B. Turcq (eds.). Restingas: origem, estrutura, processos, pp. 327-342. Anais do Simp6sio Sobre Restingas Brasileiras. Niter6i, RJ. BERGALLO, H. G. AND C. F. D. ROCHA. 1993. Activity patterns and body temperatures of two sympatric lizards (Tropidurus torquatus and Cnemidophorus ocellifer) with different foraging tactics in southeast ern Brazil. Amphibia-Reptilia 14:312-315. ___, AND . 1994. Spatial and trophic niche differentiation in two sympatric lizards (Tropidurus torquatus and Cnemidophorus ocellifer) with different foraging tactics. Austr. J. Ecol. 19(1):72-75. BRATISTROM, B. H. 1965. Body temperatures of reptiles. Amer. MidI. Nat. 73:376-422. HUEY, R. B., AND E. R. PIANKA. 1977. Patterns of niche overlap among broadly sympatric versus narrowly sympatric Kalahari lizards (Scincidae: Mabuya). Ecology 58:119-128. _ _ _, AND . 1981. Ecological correlates of foraging mode. Ecol ogy 62:991-999. JESUS, R. M. 1988. A reserva florestal da C. R. V. D. em Anais do VI Congresso Florestal Estadual, pp. 59-112. Nova Prata, RS, Brasil. MAGNUSSON, W. E., L. J. PANA, R. M. ROCHA, C. R. FRANKE, L. A KASPER, AND A P. LIMA. 1985. The correlates of foraging mode in a community of Brazilian lizards. J. Herpetol. 41:324-332. PETERS, J. A, AND R. DONoso-BARROS. 1970. Catalogue of the Neotropi cal Squamata, Part II. Lizards and Amphisbaenians. U.S. Natl. Mus. Bull. 297, viii + 293 pp. REBOU
