Spisula precursor (FOSSIL) W.H. Dall, 1909 † Western Kamchatka
Mactra proaspera F. Sacco, 1900 West Africa
Oxyperas proaspersa (FOSSIL) (F. Sacco, 1901 †)
Mactra procrassa (FOSSIL) Woods, 1850 † UK, England, Suffolk
Mactra protoreevesii (FOSSIL) Noetling, 1901 † India, Meghalaya
Mactra pulchella R.A. Philippi, 1846 Japan, Aichi
Raeta pulchella (A. Adams & L.A. Reeve,1850) China, Zhejiang22,3 mm
Mactra pura L.A. Reeve, 1854 Tasmania
Mactra pusilla R.A. Philippi, 1887 New Caledonia23 mm
Anatina putatoria (FOSSIL) White, 1887 † Brazil, Sergipe
Willimactra putida (FOSSIL) Saul, 1973 † United States, California, Shasta
Mactra pyrenaicensis (FOSSIL) A.E.M. Cossmann, 1923 † France, Aquitaine
Mactra quadrangularis L.A. Reeve, 1854 China, Bo Sea19,4 mm
Mactra quadrangularis veneriformis G.P. Deshayes in L.A. Reeve, 1854 Yellow Sea55,7 mm
Mactra queenslandica Smith, 1914 Australia, Townsville21 mm
Mactra quirosana F. Hodson, 1931
Mactromeris ramonensis (FOSSIL) A. Packard & Clark,1915 † United States, California, Kern
Spisula rappahannockensis (FOSSIL) Gardner, 1944 † USA, Virginia, Surry
Spisula raveneli (T.A. Conrad, 1832) Florida58 mm
Austromactra recondita (FOSSIL) (G.P. Deshayes, 1857 †) France, Paris Basin
Mactrinula reevesii (J.E. Gray, 1837) Indonesia
Lutraria rhynchaena I.H. Jonas, 1844 South Australia83 mm
Tanysiphon rivalis W.H. Benson, 1858 Ganges Delta
Mactra rochebrunei É. Lamy, 1916 Mozambique95,6 mm
Barymactra rostrata (L. Spengler, 1802) Mexico
Austromactra rufescens (J.B.P.A. Lamarck, 1818) Australia, Albany68 mm
Eastonia rugosa (FOSSIL) (G.S. Helbling, 1779 †) Spain57 mm
Mactromeris rushi (FOSSIL) Wagner & Schilling,1923 † USA, California, Fresno
Darina rustica M. Huber, 2010 Argentina30 mm
Spisula sachalinensis (L. von Schrenck, 1862) Taiwan Strait106 mm
Trinitasia sanctiandreae (FOSSIL) (C.J. Maury, 1925 †) Colombia, La Chorrera
Lutraria sanna (FOSSIL) B. de Basterot, 1825 † France, Aquitaine
Mulinia sapotilla (FOSSIL) W.H. Dall, 1898 † Florida
Mactra sauliana J.E. Gray, 1838 Senegal, Dakar
Lutraria scaldensis (FOSSIL) Urk, 1980 † Belgium