Larval food habits of the forest green tree frog (Rhacophorus arboreus) were studied in the laboratory. Tadpoles were fed single food items (leaf litter, algae or sludgeworms) individually, and their survival, growth, and development were compared. All of the algae-fed and 38% of the worm-fed tadpoles metamorphosed, but none of the litter-fed tadpoles did. Algae-fed tadpoles developed faster than wormfed ones and their size at metamorphosis was the same. Algae are the most suitable food item for the larvae of Rhacophorus arboreus.
This study developed a set of universal primer of the PCR in mitochondrial DNA D-loop region that is applicable to almost all species of Japanese salamanders. As the first step, the sequence of 1316 base pairs (including a part of unknown sequences of about 340bp) in the region of tRNApro-D-loop-tRNAphe-12SrRNA was determined for the mitochondrial DNA extracted from muscle tissue of the Oita salamander (Hynobius dunni). Using the sequence, we developed a set of PCR primer of HDL-F1 (5'-GGC ACC CAA AGC CAA AAT TC-3') and HDL-R 4 (5' TAG ATC CAG ACC AGA TGC CGG-3') to target 222 bp in the former part of the D-loop region. This primer set should be useful for studies to analyze the intra-specific genetic variations because this part of the D-loop region shows a high rate of base displacement. In this study, we also show sequences of the former part of the D-loop region (222 bp) for 5 Japanese salamander species cut by the present primer set.
During a survey of the freshwater turtles in the Inbanuma basin, central Japan, Asian brown pond turtles Mauremys mutica were recorded at 6 of 50 sampling sites from 2000 to 2004. Of a total of 32 turtles collected, 29 were captured within a 2.5 km section of the Takasaki Stream. Ten juvenile turtles presumed to have hatched in the wild were also captured. Based on these records, we suggest that M. mutica has established an incipient population in this area. Examination of morphological characters indicates that the Inbanuma population of M. mutica is a mixture of two subspecies from various localities.
Xenopus laevis, a frog commercially traded as a laboratory and pet animal, was first recorded in the wild at four localities in the Kanto plain, central Japan. Frogs found in the Tonegawa River might be a feral population established in the past decade because several X. laevis have been collected intermittently since the late 1990's. It is uncertain, however, whether Xenopus found at three other localities (Hasuike Pond in Fujisawa City, Inbanuma Pond in Shisui Town, and A ditch in Nagara Town) have established feral populations because there are few or no subsequent capture records since the first record at each locality.