襞鱼 'bì yú'

襞鱼是脊椎动物中咬合速度最快的物种，尽管是生活在水的密度相当于空气密度800倍的深海，襞鱼的嘴开合的速度仍然接近于子弹的速度。

百度翻译提供：

Plica is the species with the fastest bite speed among vertebrates. Although it lives in the deep sea where the density of water is 800 times that of air, the speed of opening and closing the mouth of plica is still close to the speed of bullets.