Crassostrea

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

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.

[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] Extant species are:[2] Fossil species include:[5] 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.

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