Murchisonellidae: Koloonella coacta (Watson, 1886) (‘forced murchisonellid’)
Synonym(s): coacta Watson, 1886.
Typical shell-length 3.0 mm. Lives subtidally and offshore as an ectoparasite of other invertebrates. Native. Endemic to northern and eastern Australia (NT, QLD, NSW and TAS).
Order: Lower Heterobranchia