The phylogenetic relationship of Draco fimbriatus with other congeneric species was inferred from 848 base pairs of the mitochondrial 12S and 16S rRNA genes. The results confirmed that the closest affinity was between D. fimbriatus and D. maculatus. Our results also suggested that D. lineatus diverged first, followed by the D. cornutus-D. volans cluster, D. dussumieri, the D. fimbriatus-D. maculatus cluster, and D. blanfordii in that order, leaving D. obscurus and D. taeniopterus as monophyletic. The taxonomic diversity of Draco in each area of Southeast Asia appears to have increased through multiple colonizations rather than through in situ diversifications.

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An adult male Mabuya, recently collected from Lanyu Island, Taiwan, was identified as Mabuya cumingi, a species hitherto known only from Luzon Island of the Philippines, on the basis of small body size (56.6mm in snout-vent length), embossed dorsal head scales, five scales beneath toe I, and the presence of a dark middorsal stripe. Occurrence of this species on Lanyu Island was also confirmed by additional sighting records. Mabuya cumingi is regarded as a fourth reptile species representing a dispersal to this island from the Philippines.

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The size and shape of 15 species of frogs (Ranidae and Rhacophoridae) from southwestern India were investigated by light and scanning electron microscopy. Most species of the genus Rana had spermatozoa of a typical form, with a thick sperm head and a thin tail. In contrast, Rana beddomii had long spermatozoa with a slender and densely coiled sperm head and a thick tail, suggesting the validity of the genus Indirana. The sperm head of Nyctibatrachus major was thick and very loosely coiled. Differing from Rhacophorus species from east Asia, the sperm head of Rh. malabaricus was not coiled. Polypedates maculatus had very long thread-like spermatozoa as in Rh. malabaricus. Spermatozoa of all examined species of the genus Philautus had a crescent-like sperm head and a thin tail resembling the head and tail of the genus Chirixalus.

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We karyotyped five species of the agamid genus Gonocephalus, G. chamaeleontinus, G. liogaster, G. bellii, G. grandis (from Peninsular Malaysia), and G. robinsonii. Of these, karyotypes of the first four species had several chromosomal characteristics exclusively shared with the previously reported karyotypes of G. miotympanum and G. grandis (from Borneo), such as the diploid chromosome number (42) and the presence of 22 biarmed macrochromosomes. This seems to support the monophyly of those four species and G. miotympanum, probably along with some other species of the genus not yet karyotyped. This hypothesis is premised on our finding of distinct chromosomal characteristics that are indicative of highly derived states in the agamid karyotypes. The karyotype of G. robinsonii, while remarkably different from other congeneric karyotypes in exhibiting much smaller diploid (32) and biarmed macrochromosome numbers (12), share these and other chromosomal characteristics with several Australian species. It seems unlikely for the karyotype of G. robinsonii to directly emerge from other congeneric karyotypes or vice versa. We conclude that the inclusion of this species in Gonocephalus would render the genus paraphyletic.

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Lines of arrested growth (LAGs) appearing in bone sections are useful for age estimation. They also indicate the past growth process in amphibians in temperate zones. Several back-calculation formulae (BCFs) use LAGs to estimate an individual's body size at an earlier time based on the current body size. In order to evaluate the validity of these BCFs, we conducted a mark-recapture and skeletochronological study of female Rana japonica in Higashi-Hiroshima, Japan, from 1995 to 1999. The body sizes of 31 recaptured frogs were back-calculated using eight different BCFs and were compared with the frogs' actual body sizes as measured at the previous capture. The most accurate estimation was made by the simplest BCF (Dahl-Lea method) without any regressions between body size and bone diameter; that is, L_i=L_c(D_i/D_c) (L: snout-vent length, D: bone diameter, c: at the time of capture [recapture], i: at the i-th winter).

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In this study, by converting the colors of the first coastal scutes (C1) in the hawksbill turtle, Eretmochelys imbricata, into numerical values by the shade (256 phases), it became possible to fully analyze the brightness of the carapace. Two thousand seven hundred fifty-six C1s of hawksbill turtles that had been captured in the Cuban sea from 1993 through 1994 were used. The relationship between the brightness and the width of the first costal (C1W) was examined. The results showed no correlation between brightness and C1W. However, C1 with barnacles tends to have greater C1W (27.1±2.8cm), while no barnacles were found on C1 with a width of 20.3cm or less. C1 with barnacles, compared to C1 without, was low in brightness (somewhat dark) in terms of statistical significance.

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Characteristic defensive behaviors of snakes and their ecological and morphological correlates have been well documented. Biological interpretations of these characteristics, however, often suffer from a paucity of information on actual predators of snakes. Concerning natural predators of Japanese snakes, neither quantitative data nor a systematic review are available. Here, we review and synthesize the published accounts of predators of snakes in Japan. We confirmed 59 species/subspecies of predators and 21 species of prey snakes. We hope that this review will stimulate biologists and naturalists to record further predatory events on snakes and help clarify the defensive mechanisms of snakes.

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