Thermal characteristics of an Iguanian lizard, Oplurus cuvieri cuvieri, were examined in a tropical dry forest of northwestern Madagascar. This lizard is an arboreal, strictly diurnal sit-and-wait predator feeding mostly on insects. A field study was conducted from mid-September 1997 to mid-January 1998 and from late-September to mid-November 1998. Ambient air temperature significantly affected body temperature, but sex, snout-vent length, month, perching height, and posture of perching lizards did not show significant effects on body temperature. Effects of time and interaction between ambient temperature and time were significant in the first half of 1997 (dry season) and 1998, but not in the latter half of 1997. Overall body temperature was significantly correlated with ambient temperature, and slopes between them did not significantly deviate from one. However, slopes varied with time of day, and significant correlation between ambient and body temperatures diminished in the midday period. Body temperature was significantly higher than corresponding ambient temperature. In the rainy season, when ambient temperature decreases, the lizards seemed to regulate its body temperature to some extent by selecting hotter microhabitat (the ground). Collectively, although the study site is a relatively open, deciduous forest, where direct solar radiation for thermoregulation by basking is available, O. c. cuvieri exhibits intermediate features between thermoregulator and thermoconformer, having mixed characteristics of both types.

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A new species of Cnemaspis is described from Phuket Island, southern Thailand. The new species can be distinguished from congeners from Southeast Asia by the following combination of characters: SVL to 29.1mm, two semi-circular supranasals separated by a single scale; three postnasals bordering nasal; four scale rows separate orbit from supralabials; posteriorly, each postmental bounded by three smooth, rounded, and juxtaposed scales; scattered spinose paravertebral rows of tubercles on dorsum; gular and pectoral scales unicarinate; abdominal scales not elongated, smooth; tail segmented, with enlarged flattened scales forming whorls, a single pair of spinose postcloacal spurs present; median subcaudals not enlarged, smooth; supralabials (to midorbit position) 6-7; infralabials 6-7; lamellae under toe IV 16-17; midventrals 26-32; and adult males lack preanal and femoral pores.

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The Kikuzato's brook snake, Opisthotropis kikuzatoi, is a highly endangered aquatic or semiaquatic species endemic to Kumejima Island of the Okinawa Group, Ryukyu Archipelago. Field studies were carried out for some ecological aspects of this species by visiting its habitat almost every month from April 1996 to March 1997. The results demonstrate that the snake is active almost throughout the year. It is also suggested that the snake tends to be diurnal in the warmer season, and nocturnal in the cooler season. Observations on a case of autonomous emergence onto the land, very slow growth, and predation on small crabs, are also provided.

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Oviposition sites of Buergeria japonica were surveyed in portions of two streams near the coast on Okinawa Island, Ryukyu Archipelago, Japan. Twenty-five and 52 oviposition sites were found. At all these sites the salinity was constantly 2‰ or less despite occasional exposure of these portions to the sea breeze. The pH value at the sites, ranging from 7.7-10.2, never dropped into the acid range. There were no significant differences in water depth or distance from the bank at the oviposition sites between the two streams, despite the prominent differences in some topographic characters, such as maximum water depth and stream width.

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