Skeletal remains of the geoemydid turtle, Mauremys mutica, were recovered from the lower layer of the Tugurubama archeological site on Yonagunijima Island, which corresponds to the period from the late middle to early late Holocene (ca., 4,000 yBP). These represent the first concrete evidence for the prehistoric occurrence of this turtle in the Yaeyama Islands and offer strong support for the indigenous nature of the current Yaeyama populations of M. mutica.

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We conducted a radio-tracking study on Rhabdophis tigrinus to assess its spatial ecology in the Ashiu Forest Research Station, Kyoto, Japan from 2009 to 2010. The study site is located in a temperate mountain area and includes forests, grasslands, a river, open riverbanks, and small brooks. We estimated the width and area of home ranges for 11 and 10 individuals, respectively. Home range size showed a large individual variation, with home range width ranging from 97 to 997 m and area ranging from 1.3 to 11.0 ha. We did not find obvious sexual differences or effects of body size on home range size. Tracked snakes tended to aggregate in riverside areas in spring, although females were sometimes found away from the river. Compared to spring, snakes in summer and fall were relatively dispersed and more likely to be located in brookside areas or places apart from water bodies. Eight individuals moved from riverside areas to brookside areas in summer. We located hibernation sites of nine individuals. Before hibernation, four individuals moved to a mountain ridge or a steep rocky slope where snakes were never found in warmer seasons, whereas the other five individuals hibernated within their warm-season home range. Neither sex nor body size seemed to be related to the occurrence of migratory movements in summer and before hibernation. Previous studies based on visual surveys have suggested bimodal seasonal activity of R. tigrinus, with peaks in spring and fall. However, activity of the tracked snakes in our study did not decrease in summer compared to that in spring, suggesting underestimation of summer activity in the visual survey method. Our results suggest that R. tigrinus migrates to use different habitats among seasons, although there is individual variation in migratory behavior.

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Using 55 wild-caught turtles of various sizes [straight carapace length (SCL): 35–227 mm], we estimated a time span of the subadult stage extending from the onset to completion of sexual maturation in female Mauremys reevesii from central Japan. We examined serum vitellogenin (VTG, a yolk-precursor protein) levels of the 55 turtles and thereby determined the size at the onset of sexual maturation. We also sacrificed nine of these turtles (SCL: 143–180 mm) and made anatomical observations focusing on their ovaries and oviducts in order to determine size at the completion of sexual maturation. Serum VTG was detected in all females with SCL ≥155 mm but not in any female with SCL <145 mm, thus indicating that the first vitellogenesis in M. reevesii occurs when SCL has reached around 150 mm. Of the nine turtles dissected, three (SCL: 172–180 mm) had oviductal eggs, corpora lutea, and/or enlarged follicles that would be ovulated in the next breeding season, while the other turtles (SCL: 143–168 mm) did not show any anatomical evidence of full maturity. It is therefore considered that the sexual maturation of female M. reevesii is complete when SCL has reached around 170 mm. A growth curve based on the age and SCL data of the wild-caught turtles indicated that SCLs at the onset and completion of sexual maturation (150 and 170 mm, respectively) corresponded to the ages of five and seven years, respectively. The time span of the subadult stage was therefore estimated to be two years in female M. reevesii.

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We record a tree frog of the genus Liuixalus for the first time from outside of China and describe it as a new species, Liuixalus catbaensis, on the basis of a single juvenile specimen collected from Cat Ba Island, northern Vietnam. The new species is easily distinguished from all other members of the genus Liuixalus by its uniformly brick-red dorsum lacking dark markings. The biogeographical significance of finding of this species in Vietnam is briefly discussed.

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The diet of the adult Cynops pyrrhogaster was studied at a small pond on the Yachidaira high moor (1500 m asl) from 2002 to 2004. In total, 160 individuals examined by stomach flushing yielded 1518 prey items, of which most (95.7% of the total numerically) were small arthropods inhabiting the pond or surrounding land. Of these, chironomid larvae and Cladocera numerically represented 34.3% and 34.7%, respectively. By mass, Rhacophorus arboreus tadpoles, Odonata adults, Brachycera adults, and conspecific newt eggs comprised 13.7%, 11.5%, 10.7%, and 9.8% of all prey, respectively. The composition of prey items varied seasonally and annually. These results suggest that the food habits of adult C. pyrrhogaster in the alpine high moor areas are influenced by yearly and seasonal changes in various small animals in and around the ponds.

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Morphological variations were analyzed for green turtles, Chelonia mydas, on the basis of 127 individuals captured in the coastal waters of Japan. They were explicitly divided into two groups by plastral coloration—the yellow type and the black type. To statistically assess the morphometric differences between these color types, analysis of covariance was performed for each of 28 external measurements using the standard straight-line carapace length (SCL) as the covariate. Results indicated that the yellow and black types significantly differ in ratios to SCL of distances from the nuchal notch to the outermost point of boundry between the 11th and the preceding (10th) marginals, and also to the boundary of the 11th marginal, last (fifth) vertebral, and last (fourth) pleural on both sides. Such morphometric covariations with plastral coloration in C. mydas sensu lato, as well as sympatric occurrences of the two color types in the Japanese waters, collectively support the validity of the black type as a distinct species, Chelonia agassizii.

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Four species of endemic Leptobrachium are known from Borneo, two lowland species L. kanowitense and L. abbotti, a montane species L. montanum, and a highland species L. gunungense. Of these, both L. montanum and L. abotti were found to contain several cryptic species by recent molecular studies. The population from Bario, Kelabit Highland of Sarawak, is one such cryptic species and was once called Lineage 2 of L. abbotti. Our morphological survey on this population proved that it has characteristics distinct from all other congeners, and therefore, we describe the Bario population as a new species, Leptobrachium kantonishikawai sp. nov. The new species is distinguished from putative topotypes of L. montanum and L. abbotti, as well as from L. gunungense by having a grayish brown abdomen, usually vermiculated, although sometimes spotted or blotched with white, and some unique morphometric characteristics.

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In a color polymorphic snake, Elaphe quadrivirgata, adults exhibit distinct color patterns such as striped, pale-striped, non-striped, banded, and melanistic morphs. To evaluate a heredity model of color pattern polymorphism, we examined correspondence of color morphs between mother snakes and their offspring based on the quantitative evaluation of individual variation in stripe pattern vividness with digital image analysis of skin coloration. Striped, pale-striped, and non-striped morphs were recognized in adult E. quadrivirgata, but the cluster analyses revealed only two groups of hatchlings, which were characterized by the presence and absence of the stripe pattern. Because the stripes of E. quadrivirgata are expected to become vivid with growth but do not fade, hatchlings categorized as the striped morph will become the striped morph in adults, and pale-striped and non-striped morphs will differentiate from the non-striped group of hatchlings after a certain period of growth. Observed frequencies of striped and non-striped neonates hatched from the clutches laid by striped, pale-striped, and non-striped females supported the assumption that the striped/non-striped pattern polymorphism follows the rule of incomplete-dominance heredity model of one locus with two alleles and that the striped morph is dominant over the non-striped morph.

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Xenopus tropicalis has many advantages as a next-generation model animal for biological research. However, the temperature tolerance range of this frog is narrow, making transportation of live specimens difficult under extreme air temperatures in the summer and winter. This seasonal constraint diminishes the usefulness of X. tropicalis as an experimental animal, so an improved transportation method is required. To overcome this challenge, we conducted: (1) survival experiments under extreme temperature conditions; (2) tests of thermal retention abilities of a unique transport container system; and (3) actual transport experiments. Survival experiments indicated that 14–31C was a safe temperature range for 48-h survival of adult X. tropicalis (48 hours corresponds to the standard domestic transport time expected for delivery service companies in Japan). The container system built here was able to maintain safe temperatures over 72 h when outside temperatures were extreme, and it worked better in combination with a plastic box frog cage. The effectiveness of the transport container was demonstrated by actual transport experiments performed during the summer and winter. The survival rates of the frogs were 100% with the container system. Because the transport container can maintain mild temperatures internally over 72 h, this container system can be used to transport many different temperature-sensitive organisms.

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To develop ovulation induction techniques, we investigated the effects of follicle-stimulating hormone (FSH) administration on ovulation in captive hawksbill turtles Eretmochelys imbricata. Porcine FSH preparation was administered by intramuscular injection to four hawksbill turtles with fully-developed follicles (21.6–23.8 mm, measured using ultrasonography) in July or August 2009. Blood samples were obtained and subjected to plasma progesterone measurement, and ovaries and oviducts were observed by ultrasonography just before, and 1–6 days after, FSH administration. One day after the administraion, the plasma progesterone concentration significantly increased from the basal level (<0.01–0.3 ng/mL) to 0.8–5.1 ng/mL and then dropped to nearly the basal level within 2–4 days. The formation of eggshells was observed two days after FSH administration. These data collectively indicate that in hawks-bill turtles FSH administration effectively induces ovulation, progesterone secretion, and egg formation.

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