Usage examples (4)

• Unionidae are dioecious, meaning they have separate sexes.
• In North America, freshwater mussels (Unionidae) are declining at a catastrophic rate.
• A little later he put Hyatt at work on the Unionidae, studying the anatomy as well as the shells.
• The native freshwater bivalves of Illinois represent three families, of which the great majority belong to the Unionidae -- hence the term "unionid," which is often used...