Diagnosis | Holectypoida with:
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Range | Middle Jurassic (Bajocian) to Late Cretaceous (Maastrichtian); Europe, Middle East, North America and the Caribbean. |
Remarks | Readily distinguished from Holectypina by the aboral rather than oral periproct. Distinguished from Anorthopygidae by having the periproctal opening in broad contact with the apical disc. |