Family Cardiidae

Shell size to 67 mm; shell rounded, inflated. Sculpture of 27-32 strong radial ribs bearing sharp scales. Umbones central. Internally glossy. Color creamy-white to tawny-gray, with yellowish, orange, brownish and/or purplish patches. Internally bright salmon, reddish, and/or purple. Albinistic specimens are sometimes found on the barrier islands of SW Florida. The albinistic specimen illustrated was found by José H. Leal on March 20, 2010, under the Sanibel-Captiva Bridge on Blind Pass.

Shell size to 45 mm; shell delicate, compressed, gaping at posterior end. Sculpture of about 12 radial ribs bearing short spines near margin of shell. Color whitish, pink, light-purple, reddish-brown, mottled with darker tones; rarely all orange.

Shell size to 63 mm; shell thin, light, inflated, ovate. Surface smooth, sometimes polished. Umbones rounded. Palial line simple. Ventral margin finely crenulated. Color cream or light-yellow, with yellow, orange, or brownish marks. Interior cream. Previously in this guide as Laevicardium oviputamen (Reeve, 1844), which is a junior synonym of L. serratum. Do not confuse with Laevicardium laevigatum, which is an Indo-West Pacific species.

Shell size to 25 mm; shell smooth, polished, triangular, moderately inflated. Color white or cream with delicate shades of brown or rose; sometimes with strong, brown zigzag streaks. Common offshore; became common on Sanibel beaches after 1995-1996 beach nourishment project.

Shell size to 25 mm; shell thin but strong, inflated, smooth, ovate. Surface smooth, but with microscopic pimples arranged in concentric lines. Color cream with delicate, zigzag purplish marks; shell interior usually yellow.

Shell size to 125 mm; shell very large for family, inflated, obliquely ovate. Sculpture of about 32-36 rounded, smooth radial ribs. Umbones rounded. Palial line simple. Margins crenulated. Color pale-tan to yellowish-brown, mottled irregularly with red-brown. Posterior slope mahogany-brown. Interior salmon-pink.As it often happens with other species of the family Cardiidae, the Atlantic giant cockle uses its muscular foot to leap away, in pole-vault fashion, from attacking predators. The photos of the live cockle in this feature were taken by Dr. José H. Leal in late June 2015, during a low-tide beach walk at Bunche Beach, in Fort Myers. The cockle’s "L-shaped" foot, mottled with reddish-brown flecks, is visible on the top part of the photos.

Shell size to 50 mm; similar to Trachycardium egmontianum but with more oval outline. Sculpture of 20-40 radial ribs bearing sharp scales. Scales less prominent on central ribs. Albino shells not uncommon.

Shell size to 40 mm; shell thick, quadrangular in outline, showing a distinct groove from umbo to mid-posterior margin. Posterior slope concave. Sculpture of about 35 ribs covered with scale-like lamellae. Color whitish with reddish-brown smudges. Differs from the similar Americardia media, among other features, by ribs that are triangular, instead of rectangular, in cross-section, and by the more finely imbricate nature of the scales on the ribs.