Mercenaria
Mercenaria is a genus of edible marine bivalves in the family Veneridae, the Venus clams. The genus includes the quahogs, consisting of Mercenaria mercenaria, the northern quahog or hard clam, and M. campechiensis, the southern quahog, both important species for human consumption.
Image:Mercenaria081111.jpg|thumb|150px|left|Left valve interior of ''Mercenaria mercenaria''
Species
The World Register of Marine Species accepts the following extant species as valid:- Mercenaria browni Petuch & Berschauer, 2019
- Mercenaria campechiensis – Southern quahog
- Mercenaria hartae Petuch, 2013
- Mercenaria mercenaria – Northern quahog
- Mercenaria stimpsoni – Stimpson's hard clam
- Mercenaria texana
Fossils species
Several other species are known only from fossils. These mollusk are known since the Upper Oligocene. Fossil shells have been found in the sediments of Russia, Japan, Indonesia, Haiti, United States, and Brazil. At least the following species or subspecies are known from fossils:- †Mercenaria blakei Ward 1992
- Mercenaria campechiensis Gmelin, 1791
- *†Mercenaria campechiensis carolinensis Conrad 1875
- *†Mercenaria campechiensis rileyi Conrad 1838
- *†Mercenaria campechiensis tridacnoides Lamarck 1818
- †Mercenaria capax Conrad 1843
- †Mercenaria cuneata Conrad 1869
- †Mercenaria druidi Ward 1992
- †Mercenaria ducatelli Conrad 1838
- †Mercenaria erecta Kellum 1926
- †Mercenaria gardnerae Kellum 1926
- †Mercenaria langdoni Dall 1900
- Mercenaria mercenaria
- *†Mercenaria mercenaria notata Say 1822
- †Mercenaria nannodes Gardner 1947
- †Mercenaria permagna Conrad 1838
- †Mercenaria plena Conrad 1869
- *†Mercenaria plena inflata Dall 1903
- *†Mercenaria plena nucea Dall 1903
- †Mercenaria problematica
- †Mercenaria prodroma Gardner 1947
- †Mercenaria tetrica Conrad 1838
- †Mercenaria yokoyamai
- †Mercenaria violacea Schumacher 1817