Original paper

On the Austrotrigoniinae (Bivalvia: Trigonioidea); their evolution and classification

Cooper, Michael R.

Abstract

The subfamily Austotrigoniinae is a Gondwanic endemic of controversial standing. It was introduced (Skwarko 1968) to comprise only Early Cretaceous Austrotrigonia and Late Triassic Prorotrigonia, but its status and position has been discussed and disputed by many subsequent workers. In order to establish the systematic position and content of Austrotrigoniinae, the evolutionary history of the lineage is tracked. This demonstrates that Austrotrigonia is part of an important phyletic line (Nakano 1970a, b) dating back to the Bajocian. Together Austrotrigoniinae, Pleurotrigoniinae and Neotrigoniinae define a significant branch of the evolutionary tree and here are united as the family Pleurotrigoniidae. One new tribe (Papuagoniini) and eight new genera (Coxitrigonia, Kitchingonia, Nambangonia, Neopisthotrigonia, Ghuneriella, Kellygonia, Querandigonia, Papuagonia) are introduced.

Keywords

austrotrigoniinaenew taxapleurotrigoniidaephylogenybivalviatrigonioideaclassification