Caryocorbula swiftiana C.B. Adams, 1852 has a strongly inequivalve shell (the left and right valves have different sizes). The shell has pointed posterior region that is often extended by calcified periostracum, a radial fold or ridge is present, sculpture of irregular commarginal ridges, shell color white to light gray. Internally often whitish, or with brownish, orangish, or yellowish hues. The shell in the image is a single articulated pair, part of a larger collection of loose valves of the same species found by Susan Hewitt in December 2016 at the Captiva side of Blind Pass.
