Four cases of cannibalism among Dolichophis jugularis (Serpentes: Colubridae) are reported from Cyprus and Turkey. The number of cannibalism records for this species thus rises to at least six. Due to its opportunistic euryphagy, D. jugularis is potentially cannibalistic. Although pure opportunism cannot be ruled out, cannibalistic behaviour may be enhanced in this species by conditions such as starvation.

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We compared larval life history between two populations of Hynobius boulengeri from Kyushu, Japan, one from Takachiho on the Sobo-Katamuki Mountains and the other from Kinko on the Osumi Peninsula. They showed variation in life history which seems to be induced partially by differences in water temperature and food availability, but may also reflect differences at the genetic level. Larvae from Takachiho, where the water temperature was lower in winter, developed more slowly but grew more quickly under higher summer temperatures and by eating larger prey than larvae from Kinko. In Takachiho, most larvae overwintered once or twice, and in one case, three times. In contrast, larger numbers of larvae metamorphosed without overwintering in Kinko. Takachiho larvae were larger at metamorphosis (SVL=ca 39 mm in average) than Kinko larvae (ca. 31 mm), and this difference is thought to affect the body size difference in adults. The relatively large mouth in Takachiho larvae is thought to be an adaptation not to cannibalism, but to larger prey. The relatively small mouth in Kinko larvae, unique among larvae of H. boulengeri populations and its ally, H. hirosei, seems to be also constrained by genetic factors.

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Bufo marinus is a large toxic toad that was recently introduced to Ishigakijima of the Yaeyama Islands, Southern Ryukyus, Japan. In a previous study, the native Southern Ryukyu snake, Dinodon rufozonatum walli, did not die after ingestion of a single juvenile toad. Considering the current high density of the toads on Ishigakijima, however, it is highly likely that an individual snake may have an opportunity in the field to swallow more than one toad in succession. Therefore, we experimentally investigated the occurrence of voluntary multiple ingestions of juvenile toads by this snake and their effects on the snake. In addition, we obtained from the inhabitants of Ishigakijima some field records of dead snakes that had apparently been killed by the cane toads (sometimes larger than the juveniles used in our experiment). The experiment showed that the snake may often voluntarily seize two or more juvenile toads at once, and may die while swallowing them. These results and the field records suggest that the D. r. walli population on Ishigakijima has been seriously affected by the feral toad population by ingesting this toxic prey.

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We report the clutch size and egg sac morphology of Hynobius boulengeri from the Sobo-Katamuki Mountains, Kyushu. A total of 11 clutches (mean clutch size=39.2), each in a pair of egg sacs, were found in a steep, rocky stream head at about 900 m asl. on 6 May 2000 and 5 May 2001. The morphology of the egg sac was unique, having a string-like shape without a distinct whiptail structure at the free end. The clutch size and egg sac shape of H. boulengeri were most similar to those of H. stejnegeri, which occurs parapatrically with H. boulengeri in Kyushu.

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A new species of small green treefrog in the genus Litoria is described from the Lakekamu Basin, Gulf Province, southern Papua New Guinea. This species is associated with the Litoria gracilenta group on the basis of its pale canthal stripe and predominantly green dorsum, but can be differentiated from other species in the group by its more robust build (head width/snout-vent length [SVL] 0.37–0.38) and small body size (SVL of three adult males 28.3–28.7 mm). Dorsal colouration is either plain green or green with numerous small dark spots, suggesting colour polymorphism. This dark-spotted colouration is also unique amongst the L. gracilenta complex.

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Relationships between weight (W: wet or dry weights) and length (L: snout-vent length, head width, tibia length, or total length) were examined for six amphibian species of Japan. The formulae W=a L^b, expressing the relationships between those parameters, varied both among taxa and between larval and adult stages. The results suggest that researchers should make their own regressions for a target species at a given life stage in a given local environment.

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