Diagnosis | Stem group Clypeasteroida with:
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Range | Late Palaeocene to Eocene of North Africa, Arabian Peninsula, India, Madagascar and Europe |
Remarks | Distinguished from Oligopygidae only by the lack of superficial demiplates. Distinguished from Plesiolampadidae by the large perignathic girdle that is present in adults. Distinguished from Echinolampadidae by longitudinal periproct. |