Plaesiomyidae is a family of extinct lamp shells belonging to the order

Orthida Orthida is an extinct order of brachiopods which appeared during the Early Cambrian period and became very diverse by the Ordovician, living in shallow-shelf seas. Orthids are the oldest member of the subphylum Rhynchonelliformea (Articulate B ...

Fossil record

Fossils of Plaesiomyidae are found in marine strata from the

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...

until the

Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ...

(age range: from 478.6 to 418.7 years ago.). Paleobiology Database
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Genera

*†'' Austinella'' Foerste, 1909 *†'' Bokotorthis'' Popov ''et al.'', 2000 *†'' Campylorthis'' Ulrich and Copper, 1942 *†'' Chaulistomella'' *†'' Dinorthis'' Hall and Clarke, 1892 *†'' Evenkina'' *†'' Madiorthis'' Zuykov and Harper, 2008 *†'' Metorthis'' *†'' Multicostella'' *†'' Plaesiomys'' Hall and Clarke, 1892 *†'' Retrorsirostra'' Schuchert and Cooper, 1932 *†'' Valcourea''

References

{{Taxonbar, from=Q18574617 Prehistoric protostome families Prehistoric brachiopods Brachiopod families Ordovician first appearances Silurian extinctions Orthida