noun
brown frog; reddish-brown frog (Ranidae)
General term for any brown or reddish-brown frog of the family Ranidae, often used in field guides or casual observation.
田んぼでアカガエルを見つけた。
I found a brown frog in the rice paddy.
noun
Japanese brown frog (Rana japonica)
Specifically refers to the species Rana japonica, a common frog in Japan. Often called ニホンアカガエル in scientific contexts.
ニホンアカガエルは本州から九州にかけて分布している。
The Japanese brown frog is distributed from Honshu to Kyushu.
More precise scientific name for the Japanese brown frog; アカガエル can be a broader term or a shorter alternative.
Compound of 赤 (aka, 'red') and 蛙 (kaeru, 'frog'), referring to the reddish-brown coloration of these frogs.