Neobatrachia is a phylogenetically-nested anuran group and contains approximately 85% of amphibian species. It is difficult to analyze the neobatrachian mitochondrial (mt) genome due to accelerated nucleotide substitution rates and occasional gene rearrangements. To overcome these problems, we designed 15 PCR primers. These primers, together with two primers from a previous study, could amplify almost the entire mt genome in all neobatrachians tested (seven species from seven different families) without optimizing PCR conditions. Among the tested taxa, Trichobatrachus robustus (Arthroleptidae) and Hyperolius viridiflavus (Hyperoliidae) showed unique amplification patterns, suggesting occurrences of gene duplication and/or rearrangements in these mt genomes.

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Long bone histology and skeletochronology of a tropical Indian agamid lizard, Sitana ponticeriana, was studied. Long bone was histologically characterized by the presence of enlarged globular osteocytes with centrally placed nuclei that were lightly stained in juveniles. The size of the cells was reduced with growth, and osteocytes finally became elliptical with eccentric nuclei in older animals. No lines of arrested growth (LAGs) were seen in juveniles, subadults, and 40% of adults, whereas 60% of adults had 1-6 LAGs. These results indicate that the species matures within a year of hatching in the first test case and the minimal longevity in nature is six years.

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A laboratory experiment was conducted to evaluate temporal and spatial effects of predator chemicals and visual stimuli on the behavioral responses of the Rana japonica tadpoles. Nymphs of the dragonfly Anax parthenope julius were used as the predator model. Tadpoles exhibited defensive responses by reducing tail movement time associated with their activity when exposed to chemicals from the nymphs. These responses tended to be quicker and stronger as distance from the nymphs decreased. Tadpoles exposed to visual stimuli from the nymphs also exhibited similar but weaker behavioral responses. Our results suggest that in a short distance encounter defensive responses of the R. japonica tadpole are induced more quickly by chemical cues of the predator than by its visual cues. For the tadpole, detecting the dragonfly nymph by chemical cues may function as a trigger for effective predator-avoidance strategy in tadpole-dragonfly nymph interactions.

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A specimen of the Korean crevice salamander (Karsenia koreana) was found in the collection of the Institute for Amphibian Biology, Hiroshima University, Japan. The specimen was collected in 1971 from Mt. Gyeryong, South Korea by a Japanese-Korean research team. This finding indicates that this outstanding plethodontid species had actually been encountered but without appropriate recognition for more than 30 years before its official discovery in 2003 and original description in 2005. This fact suggests that old herpetological collections that have been kept unattended may yield taxonomically and biogeographically important findings.

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Recent skeletal remains of anurans, collected from Yoronjima Island of the Amami Group, Central Ryukyus, were identified by detailed comparisons with skeletal specimens representing all extant anuran species of Japan. As a result, four frog species including Rhacophorus viridis were recognized. This rhacophorid frog does not occur on Yoronjima Island at present, but its occurrence there by the middle of the 20th Century has been tentatively suspected on the basis of several museum specimens. Present finding offers a substantial support to this view, and confirms the first known case of island-level extinction of an extant native amphibian in the Ryukyu Archipelago.

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