ostracode

例句：

1. 1.The ostracode fossils found in the cave are fascinating.
   在洞穴中发现的古生代无脊椎动物化石令人着迷。
2. 2. These ostracodes were used as currency in ancient times.
   这些古生代无脊椎动物在古代被用作货币。
3. 3. The discovery of ostracodes has shed new light on the evolution of marine life.
   发现古生代无脊椎动物为海洋生物的进化提供了新的见解。