noun
montane brown frog; Nikkō frog
A species of frog (Rana ornativentris) native to Japan. The katakana name is the standard way to refer to this animal.
ヤマアカガエルは、本州の山地に生息するカエルの一種です。
The montane brown frog is a type of frog that inhabits the mountains of Honshu.
The name is a compound of 山 (yama, 'mountain'), 赤 (aka, 'red'), and 蛙 (kaeru, 'frog'), describing a reddish frog found in mountainous areas. The exact derivation is straightforward from the kanji components.