Anodonta cellensis var. beringiana Middendorff, 1851 accepted as Beringiana beringiana (Middendorff, 1851) (original description)
Cyclas calyculata var. compressa Middendorff, 1851 accepted as Musculium lacustre (O. F. Müller, 1774) accepted as Sphaerium lacustre (O. F. Müller, 1774) (original description)
Cyclas calyculata var. inflata Middendorff, 1851 accepted as Sphaerium asiaticum (E. von Martens, 1864) (original description)
Fruticicola schrenckii (Middendorff, 1850) (basis of record)
Limneus kamtschaticus Middendorff, 1850 accepted as Kamtschaticana kamtschatica (Middendorff, 1850) (additional source)
Littorina kurila Middendorff, 1848 accepted as Littorina sitkana R. A. Philippi, 1846 (additional source)
Littorina kurila var. costulata Middendorff, 1851 accepted as Littorina sitkana R. A. Philippi, 1846 (original description)
Machaera costata (Say, 1822) accepted as Siliqua costata (Say, 1822) (basis of record)
Natica aperta f. normalis Middendorff, 1851 accepted as Bulbus normalis (Middendorff, 1851) (original description)
Natica clausa var. depressior Middendorff, 1851 accepted as Cryptonatica affinis (Gmelin, 1791) (original description)
Paludinella stagnalis (Linnaeus, 1767) accepted as Eupaludestrina stagnorum (Gmelin, 1791) (basis of record)
Paludinella stagnalis var. ventricosior Middendorff, 1851 accepted as Falsicingula ventricosior (Middendorff, 1851) (original description)
Patella (Acmaea) patina (Rathke, 1833) accepted as Collisella patina (Rathke, 1833) (basis of record)
Patella (Acmaea) pelta (Rathke, 1833) accepted as Lottia pelta (Rathke, 1833) (basis of record)
Patella (Cryptobranchia) Middendorff, 1851 accepted as Lepeta Gray, 1842 (original description)
Patella caeca var. concentrica Middendorff, 1848 accepted as Cryptobranchia concentrica (Middendorff, 1848) accepted as Lepeta concentrica (Middendorff, 1848) (additional source)
Physa hypnorum var. depressior Middendorff, 1851 accepted as Sibirenauta elongata (Say, 1821) (original description)
Pilidium Middendorff, 1851 accepted as Piliscus Lovén, 1859 (original description)
Pilidium commodum Middendorff, 1851 accepted as Piliscus commodus (Middendorff, 1851) (original description)
Radix (Radix) gebleri (Middendorff, 1850) represented as Radix gebleri (Middendorff, 1850) (additional source)
Solen americanus Chenu, 1843 accepted as Machaera costata (Say, 1822) accepted as Siliqua costata (Say, 1822) (source of synonymy)
Tellina solidula f. normalis Middendorff, 1851 accepted as Limecola balthica (Linnaeus, 1758) accepted as Macoma balthica (Linnaeus, 1758) (original description)
Tritonium (Buccinum) ovoides Middendorff, 1851 accepted as Tritonium (Buccinum) ooides Middendorff, 1848 accepted as Pseudoliomesus ooides (Middendorff, 1848) (original description)
Trochus schantaricus Middendorff, 1849 accepted as Margarites schantaricus (Middendorff, 1849) (additional source)
Unio mongolicus Middendorff, 1850 accepted as Middendorffinaia mongolica (Middendorff, 1850) (additional source)
Valvata cristata var. sibirica Middendorff, 1851 accepted as Valvata sibirica Middendorff, 1851 (original description)

Syntype ZI 1140/1, 1141/2, geounit Okhotsk Sea, identified as Cryptobranchia concentrica (Middendorff, 1848)