Trigonioidea

Trigonioidea is superfamily of medium-sized saltwater clams, marinebivalvemolluscs. Within the fossil record the occurrence of this superfamily is widespread, ranging from the DevonianPeriod to Recent.

The diagnostic feature for the superfamily is the unique and complex dentition of the shell, (i.e. the interior hinge teeth that articulate the two valves). The dentition is particularly elaborate within the familyTrigoniidae.

Bieler, Carter, & Coan (2010) included the following families in Trigonioidea. Taxa marked with a † are extinct.

Trigonioidea

• TrigoniidaeLamarck, 1819
• † Newell & Boyd, 1975 (syn: Curtonotidae)
• † Pérez, Reyes, & Danborenea 1995
• † Bronn, 1849 (syn: Cytherodontidae, Costatoriidae, Gruenewaldiidae)
• † Kobayashi, 1954
• † Newell & Ciriacks, 1962
• † Newell & Boyd, 1975
• † Pojeta & Zhang, 1984