Superfamily Paeckelmanelloidea Ivanova, 1972

Diagnosis (emended)

Moderately to strongly transverse shell with maximum of width at hinge line; flanks usually with simple ribs, rarely smooth; stratigraphically younger forms sometimes with bifurcations; fold and sulcus smooth or with median rib in sulcus and on fold, more rarely multicostate or with pair of opposed plica on both valves; ventral interarea usually moderately to very high, often catacline to procline or weakly apsacline; hinge line denticulate; microornament usually consisting of capillae and anteriorly free growth lamellae; dental adminicula usually present; vascular markings simple, radial; crural plates and dorsal adminicula lacking; ctenophoridium present.