The body of this species is small and slender. The snout is thick and the canthus blunt. The hindlimbs have well developed webbing, but the forelimb has none. The mean snout to vent length for males is 28 mm (range 25-30) and for females it is 35 mm (range 27-37). There is a pair of slit-like vocal openings. In males, the nuptial pads are yellow. No dorsolateral fold exists, but the supratympanic fold is very prominent. The skin on the back is full of short tubercles and ridges.
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Japan, Taiwan
B. japonica is found in both Taiwan and Japan. In Japan, the species is specifically found on the Ryuku archipelago (or Nansei Islands). It can be found in a wide variety of habitats including, lowlands, near the seashore, and the forests in mountainous regions. The species usually lives on the ground or on rocks, and is seldomly found in trees.
Life History, Abundance, Activity, and Special Behaviors
Buergeria japonica has limited breeding sites. Tadpoles on this island were found in hot springs, and a new study (Komaki et al., Amphibia-Reptilia 2016) reports on the thermal tolerance of the species. The highest temperature of a pool occupied by tadpoles was 46.1 °C. Experiments show that this is very close to the critical thermal maximum of the species. Other frogs are known to inhabit hot springs but this is the highest temperature recorded in nature.
Possible reasons for amphibian decline
General habitat alteration and loss
Komaki, S., Lau, Q., Igawa, T. (2016). ''Living in a Japanese onsen: field observations and physiological measurements of hot spring amphibian tadpoles, Buergeria japonica.'' Amphibia-Reptilia, 37(3), 311-314.Komaki, S., Lau, Q., Igawa, T. (2016). ''Living in a Japanese onsen: field observations and physiological measurements of hot spring amphibian tadpoles, Buergeria japonica.'' Amphibia-Reptilia, 37(3), 311-314. [link]
Maeda, N. and Matsui, M. (1990). Frogs and Toads of Japan, 2nd edition. Bun-Ichi Sogo Shuppan Co., Ltd., Tokyo, Japan.
Written by Ambika Sopory (shambika AT hotmail.com), UC Berkeley
First submitted 2000-10-16
Edited by Vance Vredenburg, updated by David Wake and Sierra Raby (2019-01-08)
Species Account Citation: AmphibiaWeb 2019 Buergeria japonica: Ryukyu Kajika Frog <http://amphibiaweb.org/species/4635> University of California, Berkeley, CA, USA. Accessed Jan 22, 2019.
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Citation: AmphibiaWeb. 2019. <http://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Jan 2019.
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