The Ocean Quahog, or Black Clam (Arctica islandica) is broadly distributed in the boreal-temperate zone of the North Atlantic. It is found from the Barents Sea (Arctic Ocean north of Scandinavia and Russia) to the Gulf of Cadiz (south of Portugal) in the eastern Atlantic (where it is abundant in some regions characterized by important oceanographic fronts, such as Iceland and the boundary between the lrminger and East Greenland currents) (Scourse et al. 2006) and from Newfoundland (Canada) to North Carolina (U.S.A.) in the western Atlantic, where it is a is a common beach shell from Cape Cod northward. It is found in sand at depths from 5 to 500 meters (Scourse et al. 2006). This orange-fleshed clam, which may reach 10 cm in size, is fished commercially to a limited degree from Rhode Island south to Virginia (U.S.A.). (Abbott 1968; Morris 1973; Gosner 1978; Rehder 1981)
The Ocean Quahog may have the longest lifespan of any animal known. These clams mature at 10 to 32 years of age (Abele et al. 2009), but individuals more than 100 years old are common and reported maximum ages from various studies are 225, 268, and 374 years old. Patterns of shell growth in these clams have been used to infer historical climate changes at a range of time scales. (Schöne et al. 2005 and references therein; Scourse et al. 2006; Abele et al. 2008). These clams have also been investigated by researchers studying cellular, molecular, and genetic aspects of aging (Abele et al. 2008, 2009; Bodnar 2009).
