We describe morphological changes observed throughout the embryonic development of Mauremys japonica, a geoemydid species endemic to Japan. Eggs laid in captivity were incubated under two different temperature conditions, 26C and 30C. A total of 185 embryos and seven hatchlings were observed. We divided the whole embryonic development into 26 stages on the basis of morphological criteria previously proposed for Chelydra serpentina. Eggs of the turtle developed faster at 30C (taking 44–47 days for completion of the whole process) than at 26C (56–64 days). As has been reported previously, embryos of M. japonica developed to males after being incubated at 26C and to females at 30C, but without any visually recognizable differentiation in external morphology. Comparisons of embryos between M. japonica and three other testudinoid turtles revealed that the carapace of M. japonica started pigmentation at stage 18, i.e., earlier than the other three species by two stages.

To demonstrate the annual ovarian cycle of a multiclutched turtle Chinemys reevesii, we quantified vitellogenin (VTG, a yolk-precursor protein) in the serum collected monthly from turtles kept in an outdoor enclosure. We also sacrificed wild adult females (one or two individuals per month) captured from a river site in Kyoto, Japan, and observed oviductal eggs and follicles assigned to five size classes: C₁ to C₅, in ascending order. The seasonal variation in the serum VTG level showed a sharp peak in late spring and a broad peak during autumn, indicating that vitellogenesis accelerated rapidly in spring, decreased in summer, increased slowly but steadily in autumn, and ceased in winter. From May to July, ovulations occurred in succession preceded by the C₄-to-C₅ growth of follicles, but without substantial growth of C₁–C₃ follicles. The vernal peak of vitellogenesis would therefore contribute largely to the sequential growth of the follicles prepared for the second and third clutches of the breeding season. In August, when the successive ovulations had been completed, no remarkable growth of C₁–C₃ follicles was observed anymore, reflecting the ovarian quiescence. Newly-formed C₁ follicles appeared in September when C₂ and C₃ follicles markedly increased in number but C₄ and C₅ follicles were still absent. In October and November, C₄ and C₅ follicles were observed again, suggesting that the follicles for the first clutch of the next breeding season reached preovulatory size before hibernation. The production and remarkable growth of follicles occurring from September to November would account for the broad peak of vitellogenesis in autumn. Thus the observed seasonal variations in the serum VTG level and follicular growth were concordant with each other.

A recent taxonomic study revealed that the name Rana okinavana Boettger, 1895 is a subjective senior synonym of R. psaltes Kuramoto, 1985 from the Yaeyama Island Group of the Southern Ryukyus and Taiwan. This led the brown frog of the genus Rana from the Okinawa and the Amami Island Groups of the Central Ryukyus, long been referred to as R. okinavana in various fields of zoology, to be unnamed. Moreover, molecular phylogenetic analyses revealed that the brown frogs from the Okinawa and the Amami Groups are so divergent genetically as to be recognized as two distinct species. Because there are no available names for these brown frogs, I describe the populations from the Okinawa and the Amami Groups as two new species, R. ulma and R. kobai, respectively.

Adult sex ratio is considered to be a key factor in understanding sexual selection, mating behavior, life history and population dynamics. Following Fisher (1930), a general consensus was formed that sex ratio tends to be largely balanced. However, gainsaying this, large variations in sex ratio have been reported among populations and species of amphibians. There is little information on sex ratio in natural populations of Japanese hynobiid salamanders. To help fill this gap, we conducted a long-term census of a population of Hynobius tokyoensis from 1976 to 1985 and estimated the adult sex ratio (the proportion of males within the population) at 0.578 from data gathered during eight non-breeding seasons. The bootstrap 95% confidence interval was 0.516–0.641. The study showed that the adult sex ratio was significantly biased toward males in the population studied; it was nearly 1.5:1 (males:females). Age at first reproduction is 1 year later in females, which suggests that the most likely factor driving the unbalanced sex ratio is the differential maturation rate between the sexes.

We studied the diet of a population of Senegal running frogs Kassina senegalensis, a ground dwelling hyperoliid. Prey inventories were collected in May by stomach flushing 27 male and 28 female frogs from one population from Bénoué National Park, Cameroon. Sexes did not differ in body size, or size or number of prey items. The most frequently taken prey item was Orthoptera (36%) and Hymenoptera (24%) and Aranae (10%) followed it. The proportion of the 1087 prey samples in the litter did not differ significantly from 625 samples from the frog stomach, indicating a low degree of prey electivity. The data suggest Senegal running frog to be a wide foraging generalist.

A new microhylid frog is described from Bario, Kelabit Highlands of the State of Sarawak, in the Eastern Malaysia of Borneo Island. Morphologically, the new species differs from all known congeners in the combination of small body size; short fourth finger without subarticular tubercle; absence of subarticular tubercles on fifth toe, and usually on first finger; presence of light lateral stripe and dark inguinal spot; absence of nuptial pads and outer metatarsal tubercles. Acoustically, the new species differs from all congeners whose calls have been reported, except for K. baluensis and K. yongi, with short unpulsed notes emitted intermittently.

We examined two hypotheses regarding the function of body coloration in green anoles Anolis carolinensis. First, their bright green coloration serves as a social signal advertising territorial possession or dominance. From this hypothesis, two predictions derive: 1) most anoles with bright green coloration are adult males; and 2) adult males with bright green coloration tend to perch at higher positions to send the signal to broad areas. Another hypothesis, which is not exclusive to the former one, is that the dark coloration functions to raise their body temperature. From this hypothesis, three predictions derive: the anoles with dark (brown) coloration are 1) observed more frequently in the morning than in the daytime, 2) more likely to engage in basking behavior than in other behaviors, and 3) observed more frequently when air temperature is low. We tested these predictions in the field at the beginning of their breeding season. The results supported the advertisement signal hypothesis, but not the thermoregulation hypothesis. However, since our negative results against the latter may actually be attributable to relatively low air temperature throughout our observation period, additional observations are desired to verify rejection of the thermoregulation hypothesis as resulting from the present study.

The reproductive cycle of the skink, Cryptoblepharus poecilopleurus from the Northern Mariana Islands, western Pacific was studied by a histological analysis of museum specimens. Spermiogenesis occurred in all months examined and is likely continuous in C. poecilopleurus. Males and females mature at 37 mm SVL. Mean clutch size for 11 C. poecilopleurus females was 1.1±0.30 SD, range=1–2. The presence of reproductively active females in all months sampled except for August (n=1) suggests C. poecilopleurus females reproduce year round.

A survey was made on the literature regarding parasitic nematodes of the snakes of Japan. Twenty-six nematode species including eight of undetermined specific status were recognized. Major synonyms, when present, are listed for each species along with their host snakes.

The seacoast of Isumi City, Chiba Prefecture, Japan, is one of the northernmost nesting sites of loggerhead sea turtle Carettta caretta in the North Pacific. We observed nesting and hatching events of this species and investigated for asynchronous emergence of hatchlings from 2008 to 2010. In 2008, hatchlings emerged from all nests from July to September, but in 2009 and 2010, most clutches laid in August failed to hatch probably due to low ambient temperature resulting from low atmospheric temperature with insufficient sunshine. In one nest constructed in early July of 2010, hatchling emergence started in early September and completed in late September, 18 days after initial emergence. This extends the previous maximum records of duration of emergence from a single nest by 13 days.

The Japanese giant salamander (Andrias japonicus) is a near threatened species endemic to western Japan and is strictly protected by law. However, available information regarding the genetic diversity and genetic structure in this species, essential for its effective conservation, has been limited. We developed four microsatellite markers from A. japonicus and characterized these markers for two populations of this species, as well as for some captive Chinese giant salamanders (A. davidianus) of unknown original locality or localities. These markers, showing expected heterozygosities of 0.00–0.50 in the former and 0.63–0.89 in the latter, will be useful in documenting population genetic properties for each of the two species.

Courtship and nesting behaviors and some reproductive parameters were reported for Eleutherodactylus monensis, a terrestrial leptdactylid frog endemic to Mona Island, Puerto Rico, for the first time on the basis of captive observations of two males and one female. The female, captured in the wild in April 1996, produced a total of 22 clutches, each consisting of 5–28 eggs (±SD: 16.2±4.55), at intervals of 14–59 days (25±15.91) from December 1997 to May 2001. Approximately five days before each oviposition, the female started digging the ground with her hind-legs to make a nest concavity. Then, the female temporarily left the concavity, during which one of the males entered therein and started digging also with his hind-legs. The nest concavity eventually got to approximately 37–43 mm in diameter and 10–15 mm in depth. Then, the male moved out of it and started amplexus by mounting and holding the female. The amplectant pair moved to the concavity and the female resumed digging with her hind-legs. She, then, laid a clutch of eggs and buried it also with her hind-legs at a depth of approximately 5 to 40 mm and diameter of approximately 30 to 45 mm. The froglets, weighing 38–67 mg (57.9±6.12), hatched 15–23 days (18.8±2.86) after oviposition.