Cyrtodontidae Ulrich, 1894

Jakobsen, Kristian G., Brock, Glenn A., Nielsen, Arne T. & Harper, David A. T., 2016, A Darriwilian (Middle Ordovician) bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia, Acta Palaeontologica Polonica 61 (4), pp. 897-924 : 914

Family Cyrtodontidae Ulrich, 1894 Genus Cyrtodonta Billings, 1858

Type species: Cyrtodonta rugosa Billings, 1858 from the Black River Fauna of south eastern Canada; subsequent designation by Williams and Breger (1916).

Stratigraphic and geographic range.―The genus ranges through most of the Ordovician from the Floian to the end of the Hirnantian (e.g., Cope 2004) and represents one of the long-ranging Ordovician bivalves. Except for the Amadeus Basin material, Pojeta and Gilbert-Tomlinson (1977: 21) listed a single specimen assigned to Cyrtodonta sp. A from the Middle Ordovician Toko Group of the Georgina Basin. As the Australian specimens of the genus represent some rare Southern Hemisphere appearances they may prove useful for Middle Ordovician palaeobiogeographic reconstructions, as the genus is abundant particularly in Laurentia Pojeta 1987) but also is present in Avalonia ( Cope 1996).