noun
striped bonito; Mexican bonito
A species of bonito (Sarda orientalis).
ハガツオはカツオよりやや小ぶりだ。
The striped bonito is slightly smaller than the skipjack tuna.
市場で珍しいハガツオを見つけた。
I found a rare striped bonito at the market.
カツオ (skipjack tuna) is a more common bonito species; ハガツオ is a different species (Sarda orientalis).
The name likely derives from 歯 (ha, 'tooth') and 鰹 (katsuo, 'bonito'), referring to its sharp teeth, but the exact origin is uncertain.