Crassostrea

Crassostrea is a genus of true oysters (family Ostreidae)^[2] containing some of the most important oysters used for food.

Crassostrea Temporal range: 145.5–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Eastern oyster (Crassostrea virginica)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Ostreida
Family:	Ostreidae
Genus:	Crassostrea Sacco, 1897[1]
Species
See text
Synonyms
Ostrea (Crassostrea) Dall, 1909

The genus was recent split in WoRMS, following the DNA-based phylogenies of Salvi et al. (2014 and 2017). Pacific species were moved to a new genus Magallana. C. zhanjiangensis became Talonostrea zhanjiangensis.^[3] 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".^[4]

Species

Extant species are:^[2]

• Crassostrea aequatorialis (A. d'Orbigny, 1846)
• Crassostrea columbiensis (Hanley, 1846)
• Crassostrea corteziensis (Hertlein, 1951)
• Crassostrea mangle Amaral & Simone, 2014
• Crassostrea rhizophorae (Guilding, 1828)
• Crassostrea tulipa (Lamarck, 1819) – mangrove oyster
• Crassostrea virginica (Gmelin, 1791) – eastern oyster

Fossil species

Crassostrea gigantissima (Finch, 1824) from the Eocene of Texas.

Crassostrea gigantissima (Finch, 1824) right valve interior (Eocene of Texas).

Fossil species include:^[5]

• †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)^[6] (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^[7]

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.^[8]