The C-banded karyotype of Rana ishikawae, endemic to two of the Ryukyu Islands, Okinawa-jima and Amami-oshima, was analyzed. The karyotypes (2n=26) of the Okinawa and the Amami populations were almost identical when analyzed by the conventional Giemsa stain and there was no significant difference between each corresponding chromosome pair. However, a minor, but significant difference was detected in the presence of a specific C-band on the long arm of No. 9 chromosomes of the Okinawa population. The Amami population consistently lacked this band. The presence of an inter-island variation of Cbanded karyotypes suggests that the genotypical divergence has occurred during the geographic isolation in the geologic age between the population from Amami and Okinawa.

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Female Microhyla ornata from the Yaeyama group of the Ryukyu Archipelago have SVL 26-30mm and BW 2.1-4.1g, and contain 470-990 mature ova of 1.2mm diameter. The clutch size positively correlates with SVL, BW, and ovary weight, but ovum size shows little correlation with other parameters. Small ovum size and large relative clutch size are regarded as adaptive features for the breeding habitats.

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The external morphology of 121 geckos collected on buildings in Fukuoka City was examined. All of them were identified as Gekko japonicus by the following characteristics. They had enlarged tubercles on the back, the neck, the forearm, and the crus. They had 2-5 (average, 2.9) cloacal spurs on each side of a tail. Adult males had 3-8 preanal pores.
Forty-five percent of the specimens had caudal tubercles. More females had caudal tubercles than males. Males, with one exception, and females with SVL<53mm lacked swollen endolymphatic sacs. Of females with SVL≥53mm, 58.5% had swollen endolymphatic sacs.
SVL of adult females older than one year old was larger than that of adult males older than one year. Sexual dimorphism in head length relative to SVL was small (male/female ratio=1.013).

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