The New Zealand freshwater mussel, Hyridella menziesi, is a freshwater bivalve mollusc, in the family Unionidae.

Distribution

This species of mussel is endemic to New Zealand.

Habitat

This mussel is found only in rivers, streams, lakes and ponds favouring firm fine sandy or muddy bottoms.

Description

These bivalve shellfish grow to about 10 cm in length and are always coated with a thick, greenish-brown horny periostracum. They have an interesting juvenile stage in which the larval shellfish spends its early life attached to the body or fins of a freshwater fish.

The hinge has two small anterior pseudocardinals, plus a long lamellar lateral in the right valve, and one pseudocardinal plus two laterals in the left valve.

References

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