- Pilsbry, 1889
Mirachelus Woodring, 1928 †
Odontoturbo Loriol, 1887 †
Onkospira Zittel, 1873
Perrinia H. & A. Adams, 1854
Pholidotrope Herbert, 2012 Tallorbis...
- †Omphaloptycha †Omphalotrochus
Omphalotropis †Oncochilus †Ongleya †Oniscidia †
Onkospira †Onoba
Oocorys †Ooliticia †Oonia †Oostrombus †Ootomaria †Ootomella Opalia...
