bivalve vaginal speculum

例句：

1. 1.The bivalve shells are a popular ingredient in many seafood dishes.
   双壳类动物的贝壳是许多海鲜菜肴的常见食材。
2. 2. In the ocean, bivalves play an important role in maintaining the balance of marine ecosystems.
   在海洋中，双壳类动物在维护海洋生态系统平衡方面起着重要作用。
3. 3. The bivalve mollusks can be found in various habitats, from shallow coastal waters to deep-sea trenches.
   双壳类软体动物可以在各种环境中找到，从浅海到深海都有。