noun
Ischikauia steenackeri; wataka (species of cyprinid fish)
A freshwater fish native to Japan, specifically Lake Biwa and the Yodo River system. Scientific name: Ischikauia steenackeri.
ワタカは琵琶湖の固有種です。
The wataka is a species endemic to Lake Biwa.
The origin of the name ワタカ is uncertain. The kanji 腸香 and 黄鯝魚 are ateji (phonetic equivalents) and rarely used.