page_title: Trigoniidae
section_title: Higher level taxonomy
hierarchical_section_title: Trigoniidae / Previous research / Higher level taxonomy
caption_attribution_description: English: Laevitrigonia gibbosa from the Portland Limestone Formation (Upper Jurassic), Isle of Portland, Dorset, England.
context_page_description: Trigoniidae is a taxonomic family of saltwater clams, marine bivalve mollusks in the superfamily Trigonioidea. There is only one living genus, Neotrigonia, but in the geological past this family was well represented, widespread and common. The shells of species in this family are morphologically unusual, with very elaborate hinge teeth, and the exterior of the shell is highly ornamented.
context_section_description: Family Trigoniidae
  Subfamily Trigoniinae
  Trigonia
  Neotrigonia - the only living genus
  Agonisca
  Maoritrigonia
  Praegonia
  Minetrigonia
  ?Pseudomyophorella
  Subfamily Prosogyrotrigoniinae
  Prosogyrotrigonia
  Prorotrigonia
  Subfamily Psilotrogoniinae
  Psilotrigonia
  Subfamily Myophorellinae
  Frenguilellella
  Jaworskiella
  Myophorella
  Vaugonia
  Orthotrigonia
  Scaphotrigonia
  Subfamily Laevitrigoniinae
  Laevitrigonia
  ?Liotrigonia
caption: Internal mold of Laevitrigonia gibbosa from the Portland Limestone (Upper Jurassic), Isle of Portland, Dorset, England
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