''Crassostrea'' is a genus of true oysters (family

Ostreidae The Ostreidae, the true oysters, include most species of molluscs commonly consumed as oysters. Pearl oysters are not true oysters, and belong to the order Pteriida. Like scallops, true oysters have a central adductor muscle, which means the s ...

) containing some of the most important oysters used for food. The genus was recent split in

WoRMS The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive catalogue and list of names of marine organisms. Content The content of the registry is edited and maintained by scien ...

, following the DNA-based phylogenies of Salvi ''et al.'' (2014 and 2017). Pacific species were moved to a new genus ''

Magallana ''Magallana'' is a genus of true oysters (family Ostreidae) containing some of the most important oysters used for food. Species in this genus have been moved from ''Crassostrea'' after it was found to be paraphyletic. Species Extant species a ...

''. ''C. zhanjiangensis'' became '' Talonostrea zhanjiangensis''. The changes are not universally welcomed by oyster researchers, as ''C. gigas'' (now ''M. gigas'') is "one of the most researched species of marine invertebrate".

Species

Extant species are:

Fossil species

Fossil species include: * †''Crassostrea alabamiensis'' (Lea 1833) * †''Crassostrea ashleyi'' ( Hertlein 1943) (syn. ''Ostrea arnoldi'') * †''Crassostrea cahobasensis'' (Pilsbry and Brown 1910) * †''Crassostrea contracta'' (Conrad 1865) * †''Crassostrea cucullaris'' (Lamarck 1819) * †''Crassostrea cuebana'' (Jung 1974) * †''Crassostrea elegans'' (Deshayes, 1832) (syn. †''Cubitostrea elegans'' Deshayes 1832 or ''Crassostrea (Cubitostrea) elegans'') * †''Crassostrea gigantissima'' (Finch 1824) – Giant fossil oyster * †''Crassostrea gryphoides'' (Schlotheim 1813) * †''Crassostrea hatcheri'' (Ihering 1899) * †'' Crassostrea ingens'' (Zittel 1864) * †''Crassostrea kawauchidensis'' (Tamura 1977) * †''Crassostrea patagonica'' (d'Orbigny 1842) (syn. ''Ostrea ferrarisi'') * †''Crassostrea raincourti'' (Deshayes 1858) * †''Crassostrea titan'' (Conrad 1853) (syn. ''Ostrea prior'', ''O''. ''andersoni'') * †''Crassostrea transitoria'' (Hupé 1854) (syn. ''Ostrea maxima'') * †''Crassostrea wyomingensis''J. Haffty, R. G. Schmidt, L. B. Riley, W. D. Goss. Rocks and Mineral Resources of the Wolf Creek Area, Lewis and Clark and Cascade Counties, Montana: A Descriptive Report on an Area in the Disturbed Belt Along the Eastern Front of the Northern Rocky Mountains in Western Montana, Issues 1441-1446

Genetics

The genome of ''Crassostrea gigas'' (now '' Magallana gigas'') has been recently sequenced revealing an extensive set of genes that enable it to cope with environmental stresses.

References

Crassostrea
on britannica.com. Bivalve genera Extant Early Cretaceous first appearances Taxa named by Federico Sacco {{Ostreidae-stub