The Minor Jacknife
The Minor Jacknife (Ensis megistus Pilsbry and McGinty, 1943) has a very delicate, elongate shell with an unusual coloration that includes purplish vertical bars internally. It is a burrower, living in fine sand and mud. Minor Jacknives inhabit and can move up and down vertical or oblique, cylindrical burrows. A Minor Jacknife can burrow rapidly by using its foot as a piston inside their dwelling. In some extreme cases, individuals are known to leap out of burrows to evade predators.
The Minor Jacknife, Ensis megistus, internal (top) and external (bottom) views of the shell valves. Photo by José H. Leal.