Shell elongate or elliptical, thin to thick, and compressed (young individuals) to inflated. Anterior end rounded, posterior end bluntly pointed (males) or truncated (females). Dorsal and ventral margins usually straight. Umbos only slightly elevated above the hinge line. Beack sculpture of six to ten double-looped bars. Shell smooth, yellow or yellowish green, sometimes tan or brown, with green rays of various widths that may become indistinct in older individuals. Length to 5 inches.

Pseudocardinal teeth divergent, elongated, or triangular, thin to moderately thick; two in the left valve, one in the right (occasionally with a thin, ridgelike tooth in front). Lateral teeth straight to slightly curved, moderately long, and thin. Beak cavity moderately deep. Nacre white or bluish white and iridescent posteriorly.