This genus is very ancient. Fossils are known from the Arenig to the Quaternary (age range: from 478.6 to 0.0 million years ago). Fossils are found in the marine strata all over the world.[1]
Shells of species within this genus can reach a size of about 30 millimetres (1.2 in). They are equivalve, symmetrical, approximately triangular. The surface has fine concentric growth lines. These clams live in the muddy sand close to the sediment surface at a depth of 20 to 200 meters.[2]
Nowadays there are still many species of this genus, which have had virtually no change in the course of time. Species within the genus Nucula include:[3]