| Contents | Classes | Subclasses | Orders | Suborders | Families |
Family PTYCHOCYLIDIDAE Kofoid & Campbell, 1929
| Syns. | Ptychocyclidae, Ptychocyclididae, Ptychocylidae |
Lorica bell- or kettle-shaped, with elongate bowl; oral rim toothed or with lip; wall trilaminated, alveolar in midsection; all forms marine (mostly eupelagic); no fossil species.
| Cymatocylis Laackmann, 1910 (syn. Cymatocyclis). Very many (ca. 50) species. |
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| Favella Jörgensen, 1924. Many spp. [Genus not well assigned here?] |
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| Protocymatocylis Kofoid & Campbell, 1929 (syn. Protocymatocyclis). Few species. |
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| Ptychocylis Brandt, 1906 (syns. Pthocylis, Ptychocyclis). Several species. |
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