Geotrochus obscura J.J. Vermeulen, M. Schilthuizen& T.S. Liew MS
Helicarion obscurior Hyman,Lamborena & Köhler, 2017
Nipponochlamys obtusa (C.A. Westerlund, 1883)
Parakaliella obtusangula (O.W.H. Reinhardt, 1883)
Erepta odontina P.M.A. Morelet, 1851
Geotrochus oedobasis J.J. Vermeulen, T.S. Liew& M. Schilthuizen, 2015
Helicarion ogasawarana H.A. Pilsbry, 1902
Trochochlamys okinoshimana (H.A. Pilsbry & Y. Hirase,1904)
Inozonites orthostoma (L. Pfeiffer, 1845)
Helicarion osimakiheijii J.T. Kuroda, 1953
Parakaliella otakiana (Y. Hirase, 1909)
Irenella otareae A. Garrett
Parakaliella pagoduloides (G.P.L.K. Gude, 1900)
Geotrochus pallida (E.A. Smith, 1895)
Hemiglypta panayensis (W.J. Broderip, 1842)
Hemiglypta panayensis connectens O.F. von Möllendorff,1898
Lepidotrichia pandana (P. Bartsch, 1942)
Petalochlamys par (P.B. Schmacker& O. Böttger, 1891)
Geotrochus paraguensis (E.A. Smith, 1893)
Cucullarion parkini J. Stanisic, 1998
Sivella paviei (L.J. Morlet, 1884)
Petalochlamys perfragilis (H.A. Pilsbry, 1901)
Petalochlamys perfragilis sakui H.A. Pilsbry & Y. Hirase,1908
Dupontia perlucida (A. Adams, 1867)
Panulena perrugosa T. Iredale, 1945
Orpiella pfeifferi (R.A. Philippi, 1845)
Mathewsoconcha phillipii (J.E. Gray, 1834)
Caldwellia philyrina (P.M.A. Morelet, 1851)
Parakaliella phyllophila (A. Adams, 1868)
Helicarion planilabris J.C. Cox, 1866
Helicarion planospirus (L. Pfeiffer, 1853)
Roybellia platysoma (E.R. Sykes, 1900)
Dendrotrochus ponapensis H.B. Baker, 1941
Levidens ponderi I. Hyman, 2007
Helicarion porrectus T. Iredale, 1941