Phenotypic Features of Dimya cf. Japonica (Bivalvia, Dimyidae) from Niue Island (South Pacific) with Accounts on Its Phylogeny and Taxonomic Relationships

Abstract

ABSTRACT Phenotypic characters of the uncommon Dimya cf. japonica, based on a specimen from Niue Is. in the South Pacific, are reported to represent the enigmatic Dimyidae in a wide-ranging Bivalvia phylogenetic scenario. The main conclusion is that dimyids are placed between ostreoideans and pectinoideans. This is supported by five synapomorphies. Dimyids are closer to pectinoideans, in that they share four synapomorphies.