qiāng / jí / yú / shì / yī / zhǒng / qǐ / yuán / yú / sì / yì / nián / qián / de / gǔ / lǎo / yú / lèi

腔棘鱼是一种起源于四亿年前的古老鱼类。

The coelacanth is an ancient fish species that originated 400 million years ago.