Amphidiadema rectangularis subsp. samuelsonii

"subsp. samuelsonii" (Kjellström, 1973, p.22, fig.18) Lentin and Williams, 1976, p.61.  Holotype: Kjellström, 1973, fig.18.  Originally Deflandrea rectangularis var. samuelsonii, subsequently Deflandrea rectangularis subsp. samuelsonii, thirdly Amphidiadema rectangularis subsp. samuelsonii.  Taxonomic senior synonym: Triblastula (now Hystrichosphaeropsis) quasicribrata, according to Gocht (1976, p.322).  Age: Early-Late Maastrichtian. Parent: Amphidiadema rectangularis