Using stomach content analysis, I assessed effects of head morphology of larval salamanders (Hynobius retardatus) on the selectivity of diets in nature. Large-headed morphs of the larvae chiefly ate terrestrial invertebrates, whereas the most abundant prey item of small-headed morphs was Diptera larvae. This suggests that larvae of H. retardatus change their prey in association with the head shape. I thus consider that the flexible development of a larger head induced by larval density of this species would change their diet selection.

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The Ryukyu five-lined skink, Eumeces marginatus, is an endemic species of the central and northern Ryukyus, and is composed of two morphologically defined subspecies, E. m. marginatus from the Okinawa Group, and E. m. oshimensis from the Amami and Tokara Groups. A population of the genus Eumeces, recently found on Iotorishima Island (an uninhabited islet located north of the main island chain of the Ryukyus), resembles E. m, oshimensis in having a relatively short median white line on the tail, but is distinct from any population of E. marginatus in having more midbody scale rows. To assess the taxonomic status of the Iotorishima population from a historical viewpoint, we examined its genetic relationships with E. marginatus populations. The degree of genetic differentiation between the Iotorishima population and a population of E. m. oshimensis from Tokunoshima, northern Amami islands, was fairly low (D=0.043). Cluster analysis of genetic data also indicated that the Iotorishima population constitutes one of the two major clusters within E. marginatus together with four E. m. oshimensis populations from the northern Amami and southern Tokara islands. Thus, it is likely that the number of midbody scale rows in the Iotorishima population has increased rapidly after its relatively recent isolation. Taxonomically, the Iotorishima population seems to be most appropriately assigned to E. m. oshimensis.

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In order to assess phylogenetic relationships of a Chinese frog, Rana zhengi Zhao, 1999, the sequences of 587 base pairs of the mitochondrial cytochrome b gene are compared with six species of Japanese (R. pirica, R. ornativentris, R. japonica, R. okinavana, R. tagoi, and R. tsushimensis), one species of Taiwanese (R. sauteri), one species of Russian (R. amurensis), and two species of European brown frogs (R. temporaria and R. dalmatina). The resultant phylogenetic tree suggests monophyly of R. zhengi and these brown frogs, and the earliest divergence of R. zhengi among all the ingroup species examined. Monophyly of R. zhengi and R. sauteri was rejected. For this reason, placement of R. zhengi within the brown frogs of the R. temporaria group requires further study, and separation of R. zhengi and R. sauteri as a distinct genus or subgenus Pseudorana is not supported.

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Advertisement call structures of ten frog species, six ranids and four rhacophorids, from southwestern India were analyzed. Rana temporalis, Limnonectes limnocharis, Indirana semipalmata, Nyctibatrachus major, and Philautus cf. bombayensis had simple calls consisting either of a single note or of a series of similar notes. Limnonectes cf. keralensis and P. cf. travancoricus had a relatively long call with a well-differentiated first note, and L. syhadrensis, P. leucorhinus, and Rhacophorus malabaricus had complex call structures with a variety of call types. Several ecological notes associated with breeding, and some taxonomic problems are presented.

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Rana limnocharis from rice fields of Nara, central Japan, fed on a wide variety of prey animals. Arthropods constituted 94.8% in number and 52.9% in volume of total prey items. Among prey taxa, ants (26.9%) comprised the largest proportion in number, and earthworms (36.2%) in volume. One froglet and one tadpole were also recovered from frog stomachs. The generalized food habits of R. limnocharis would ensure the establishment of populations of this species outside its natural range.

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Monophyly of the batagurid subfamily Geoemydinae was evaluated, and phylogenetic relationships within the subfamily were inferred on the basis of 35 morphological characters. Two approaches, parsimony analysis using the branch and bound algorithm, and neighbor joining clustering of an absolute distance matrix, were used. The results of these analyses yielded phylograms that were almost identical in branching topology, and poorly supported the monophyly of Geoemydinae. This subfamily thus seems to be a metataxon, most likely consisting of the sister group of Batagurinae (Geoemyda group) and a more primitive stock of Bataguridae (Mauremys group). The latter accommodates Mauremys and Sacalia and its monophyly is not well supported. The former consists of the remaining ten geoemydine genera united by two synapomorphies-absence or reduction of the quadratojugal, and posteriorly short-sided anterior neurals. Relationships revealed by our analyses necessitate some changes in the generic classification of Geoemydinae. First of all, Cistoclemmys Gray, 1863 (type species: Ci. flavomarginata, often synonymized to Cuora Gray, 1855 (type species: Cu. amboinensis), is shown to be a valid genus closely related to Pyxidea and Geoemyda rather than to Cuora (sensu stricto). Rhinoclemmys Fitzinger, 1835 (type species: R. punctularia) is shown to be polyphyletic, and Chelopus Cope, 1870 (type species: C. rubida), is resurrected to accommodate R. rubida and R. annulata. The plastral hinge seems to have evolved three times in the Bataguridae-in the Cyclemys-Notochelys clade, Cuora (sensu stricto), and the Cistoclemmys-Pyxidea clade.

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