Figure 1 in Phylogeny of Veneroidea (Mollusca: Bivalvia) based on morphology and molecules

Figure 1. Mercenaria mercenaria, showing features of venerid shell morphology coded by this analysis. A, right lateral view of exterior of right valve. B, right lateral view of interior of left valve. C, dorsal view of articulated valves, anterior to the right. aams, anterior adductor muscle scar; aprms, anterior pedal retractor muscle scar; com, commarginal sculpture; esc, escutcheon; hp, hinge plate (with cardinal teeth); lig, ligament; ligp, ligamental pit; lun, lunule; mar, shell margin; pams, posterior adductor muscle scar; pl, pallial line; ps, pallial sinus; u, umbo.