The eggs of Carter’s freshwater mussel undergo fertilisation within a specialised area of the female’s gills, known as a ‘marsupium’. After hatching, the larvae remain in the marsupium until they are ready to be released (4).
Like other freshwater mussels, Carter’s freshwater mussel has a life cycle which involves a parasitic stage during which the larvae, known as ‘glochidia’, attach to host fish for a period of three to four weeks during spring and summer, between late September to December (6). After they have completed metamorphosis, the newly formed juvenile mussels detach from their host fish and begin life in the sediments (7) (8).
Fish from wild populations found to have attached glochidia of Carter’s freshwater mussel primarily include endemic species such as the Swan River goby (Pseudogobius olorum), southwestern goby (Afurcagobius suppositus), western minnow (Galaxias occidentalis) and western pygmy perch (Nannoperca vittata) (6). A few introduced, non-native fish may also play host to the larvae of this species (6).
The lifespan of Carter’s freshwater mussel is not known, but other species in the Hyriidae family are estimated to live for up to 20 years or more (4).