The Echinoid Directory

Key to the genera of Paleopneustidae

1a. Petals wide with broad perradial interporal zone.
Antillaster

1b. Petals narrow with interporal zone not much wider than pore zone.

Go to 2
2a. Periproct inframarginal; clearly visible in oral view.
Plesiozonus

2b. Periproct marginal; largely hidden in oral view.

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3a. Anterior of test convex; no sulcus.
Paleopneustes

3b. Anterior of test indented by sulcus.

Mortonaster