Unionidae is a family of freshwater mussels, found world-wide living buried in mud, silt or sand in rivers, streams and lakes. The shell is equivalve, nacreous and with a thick periostracum. The hinge mostly with two cardinals and two posterior lamellar teeth.

Species

• Genus Alasmidonta
  • Dwarf wedgemussel, Alasmidonta heterodon, I Lea, 1830
    
• Genus Cucumerunio
  • Cucumerunio websteri websteri, Simpson, 1902
    
  • Cucumerunio websteri delli, McMichael & Hiscock, 1958
    
• Genus Epioblasma
  • Northern Riffleshell, Epioblasma torulosa rangiana, (I Lea, 1838)
    
• Genus Hyridella
  • New Zealand freshwater mussel, Hyridella menziesi, Gray, 1843
    

References

• A B Powell, New Zealand Mollusca, (William Collins Publishers Ltd, Auckland, New Zealand 1979) ISBN 0-00-216906-1

Bivalves | Unionidae