The ocean quahog (Arctica islandica) is a species of edible clam, a marine bivalve mollusk in the family Arcticidae.

[3] An individual specimen was reported to have lived 507 years, making it the longest-lived non-colonial metazoan whose age was accurately known.

Dynamic Energy Models (DEM) predict that A. islandia's extreme longevity arises from lowered somatic maintenance costs and a low aging acceleration.

[6] This slow life style results in exceptional longevity, e.g., with a reported age, for Ming the clam, of 507 years.

This characteristic has proven useful in the science of sclerochronology, the study of periodic physical and chemical features in the hard tissues of animals that grow by accretion, and is especially valuable for modeling of paleoclimates.