• Mesostoma Deshayes, 1861 † accepted as Cerithioderma Conrad, 1860
• Mesostoma Dugès, 1830
• Mesostoma Heude, 1886 accepted as Tylotoechus Kobelt & Möllendorff, 1897
• Mesostoma africanum Kolasa, 1976
• Mesostoma ajpetri Nasonov, 1923 (uncertain > nomen dubium)
• Mesostoma andicola (Schmarda, 1859) Graff, 1882 (uncertain > nomen dubium)
• Mesostoma andrewsi Hyman, 1957 accepted as Mesostoma platygastricum Hofsten, 1924
• Mesostoma angulare Higley, 1918 (uncertain > nomen dubium)
• Mesostoma angulata Deshayes, 1861 † accepted as Trichotropis angulata (Deshayes, 1861) †
• Mesostoma antarcticum Dreyer, 1918 accepted as Mesostoma mutabile Bohmig, 1902
• Mesostoma appia Kolasa, 1984 (unaccepted > nomen nudum)
• Mesostoma appinum Kolasa & Schwartz, 1988
• Mesostoma arctica Hyman, 1938 accepted as Mesostoma arcticum Hyman, 1938
• Mesostoma arcticum Hyman, 1938
• Mesostoma armatum Fuhrmann, 1894 accepted as Castrada (Castrada) armata (Fuhrmann, 1894) Luther, 1904
• Mesostoma armeniacum Plotnikow, 1906 (uncertain > nomen dubium)
• Mesostoma aselli Kennel, 1898 accepted as Castrada (Castradella) granea Braun, 1885
• Mesostoma auditivum Forel & du Plessis, 1874 accepted as Otomesostoma auditivum (Forel & Du Plessis, 1874) Hofsten, 1907
• Mesostoma balatonicum Szigethy, 1897 (uncertain > nomen dubium)
• Mesostoma banaticum Graff, 1875 accepted as Olisthanella truncula (Schmidt, 1858) Voigt, 1892
• Mesostoma baoensis Ruebush, 1939 accepted as Mesostoma lingua baoensis Ruebush, 1939 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma benazii accepted as Mesostoma benazzii Papi, 1949
• Mesostoma benazzii Papi, 1949
• Mesostoma bistrigatum (Fabricius, 1826) Diesing, 1850 (uncertain > nomen dubium)
• Mesostoma bologoviense Plotnikow, 1906 accepted as Strongylostoma elongatum elongatum Hofsten, 1907
• Mesostoma brincki Marcus, 1970
• Mesostoma californicum Hyman, 1957
• Mesostoma cancellaroides Deshayes, 1861 † accepted as Trichotropis cancellaroides (Deshayes, 1861) †
• Mesostoma canum Weiss, 1909
• Mesostoma chromobactrum Braun, 1885 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma chromobractrum accepted as Mesostoma chromobactrum Braun, 1885 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma chusholense Ruebush, 1939
• Mesostoma climenti Nasonov, 1923 (uncertain > nomen dubium)
• Mesostoma coecum Silliman, 1885 accepted as Olisthanella coeca (Silliman, 1885) Luther, 1904
• Mesostoma columbianum Hyman, 1939
• Mesostoma craci Schmidt, 1858
• Mesostoma cracii accepted as Mesostoma craci Schmidt, 1858
• Mesostoma cracy accepted as Mesostoma craci Schmidt, 1858
• Mesostoma cuenoti Dörler, 1900 accepted as Castrada (Castrada) cuenoti (Dörler, 1900) Luther, 1904 accepted as Castrada (Castrada) lanceola (Braun, 1885) Luther, 1904
• Mesostoma curvipenis Hyman, 1955
• Mesostoma cyathus Schmidt, 1858 accepted as Mesostoma chromobactrum Braun, 1885 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma cycloposthe Dorner, 1902 accepted as Castrada (Castrada) armata (Fuhrmann, 1894) Luther, 1904
• Mesostoma delmarmola Vendrix, 1963 (uncertain > unassessed)
• Mesostoma destructum (Heude, 1885) accepted as Tylotoechus destructus (Heude, 1885)
• Mesostoma ehrenbergi accepted as Mesostoma ehrenbergii (Focke, 1836) Örsted, 1843
• Mesostoma ehrenbergii (Focke, 1836) Örsted, 1843
• Mesostoma ehrenbergii wardii Woodworth, 1896 accepted as Mesostoma ehrenbergii (Focke, 1836) Örsted, 1843
• Mesostoma evelinae Marcus, 1955 accepted as Marcomesostoma evelinae (Marcus, 1955) Noreña Janssen & Faubel, 1992
• Mesostoma ewerum Du Bois-Reymond Marcus, 1951
• Mesostoma exiguum Dorner, 1902 accepted as Olisthanella exigua (Dorner, 1902) Luther, 1904
• Mesostoma extremeniense Noreña, Campo & Real, 1999
• Mesostoma flavidum Graff, 1882 accepted as Castrada (Castrada) flavida (Graff, 1882) Luther, 1904
• Mesostoma fusiforme (Duges, 1830) Ehrenberg, 1836 (uncertain > nomen dubium)
• Mesostoma gangetica Dutta, 1925 (uncertain > nomen dubium)
• Mesostoma georgianum Darlington, 1959
• Mesostoma gonocephalum Silliman, 1884 accepted as Strongylostoma gonocephalum (Silliman, 1884) Graff, 1911
• Mesostoma gracile (Schmarda, 1859) Graff, 1882 (uncertain > nomen dubium)
• Mesostoma grata Deshayes, 1861 † accepted as Trichotropis grata (Deshayes, 1861) †
• Mesostoma griseum (Müller, 1789) Graff, 1882 (uncertain > nomen dubium)
• Mesostoma grossum (Müller, 1774) Ehrenberg, 1836 accepted as Mesostoma productum (Schmidt, 1848) Leuckart, 1854
• Mesostoma hallezianum Vejdovsky, 1880 accepted as Olisthanella halleziana (Vejdovsky, 1880) Sekera, 1906 accepted as Typhloplanella halleziana (Vejdovsky, 1880) Sekera, 1911
• Mesostoma herclotsiannum accepted as Mesostoma herklotsianum de Man, 1875 accepted as Castrada (Castrada) radiata (Müller, 1773) Graff, 1882 accepted as Strongylostoma radiatum (Müller, 1773) Örsted, 1843
• Mesostoma herclotsianum accepted as Mesostoma herklotsianum de Man, 1875 accepted as Castrada (Castrada) radiata (Müller, 1773) Graff, 1882 accepted as Strongylostoma radiatum (Müller, 1773) Örsted, 1843
• Mesostoma herklotsianum de Man, 1875 accepted as Castrada (Castrada) radiata (Müller, 1773) Graff, 1882 accepted as Strongylostoma radiatum (Müller, 1773) Örsted, 1843
• Mesostoma hirudo Schmidt, 1858 accepted as Castrada (Castrada) hirudo (Schmidt, 1858) Hofsten, 1907
• Mesostoma hystrix Schmarda, 1859 (uncertain > nomen dubium)
• Mesostoma inversum Beauchamp, 1954 accepted as Mesostoma productum (Schmidt, 1848) Leuckart, 1854
• Mesostoma jilinense Wang & Huang, 2923
• Mesostoma karrooense Dreyer, 1914 (uncertain > taxon inquirendum)
• Mesostoma lacteum Neppi, 1904 (uncertain > nomen dubium)
• Mesostoma lanceola Braun, 1885 accepted as Castrada (Castrada) lanceola (Braun, 1885) Luther, 1904
• Mesostoma lapponicum Schmidt, 1852 accepted as Mesostoma viridatum (Abildgaard, 1789) Schultze, 1851 accepted as Typhloplana viridata (Abildgaard, 1789) Ehrenberg, 1831
• Mesostoma lenticulatum accepted as Mesostomum lenticulatum Schmidt, 1852 accepted as Turbella lenticulata (Schmidt, 1852) Diesing, 1862 accepted as Promesostoma lenticulatum (Schmidt, 1852) Graff, 1882 accepted as Beauchampiella lenticulata (Schmidt, 1852) Karling, 1956 accepted as Beauchampiola lenticulata (Schmidt, 1852) Luther, 1957
• Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma lingua baoensis Ruebush, 1939 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma lingua boaensis accepted as Mesostoma lingua baoensis Ruebush, 1939 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma lingua cyathus Schmidt, 1858 accepted as Mesostoma cyathus Schmidt, 1858 accepted as Mesostoma chromobactrum Braun, 1885 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma lingua lacustris Brinkmann, 1905 (uncertain > nomen dubium)
• Mesostoma lingua lingua (Abildgaard, 1789) Schmidt, 1848 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma lingua typica Brinkmann, 1906 accepted as Mesostoma lingua lingua (Abildgaard, 1789) Schmidt, 1848 accepted as Mesostoma lingua (Abildgaard, 1789) Schmidt, 1848
• Mesostoma lugdunense De Man, 1875 (uncertain > nomen dubium)
• Mesostoma macropenis Hyman, 1939
• Mesostoma macroprostatum Hyman, 1939
• Mesostoma maculatum Hofsten, 1917
• Mesostoma magnum Kolasa & Schwartz, 1988
• Mesostoma marmorosum (Müller, 1773) Örsted, 1844 accepted as Mesostoma robertsonii Graff, 1882 accepted as Tetracelis marmorosa (Müller, 1774) Ehrenberg, 1831
• Mesostoma masovicum Dorner, 1902 (uncertain > nomen dubium)
• Mesostoma metopoglea accepted as Mesostoma metopoglena (Schmarda, 1859)
• Mesostoma metopoglena (Schmarda, 1859) (uncertain > nomen dubium)
• Mesostoma michaelseni Weiss, 1909
• Mesostoma minimum Fuhrmann, 1894 accepted as Typhloplana minima (Fuhrmann, 1894) Luther, 1904
• Mesostoma morgiense du Plessis, 1876 accepted as Monotus morgiensis (du Plessis, 1876) du Plessis, 1885 accepted as Automolos morgiensis (Du Plessis, 1876) Braun, 1885 accepted as Otomesostoma auditivum (Forel & Du Plessis, 1874) Hofsten, 1907
• Mesostoma murmanicum Nasonov, 1923 (uncertain > taxon inquirendum)
• Mesostoma mutabile Bohmig, 1902
• Mesostoma nassanoffii accepted as Mesostoma nassonoffii Graff, 1882 accepted as Olisthanella nassonoffii (Graff, 1882) Luther, 1904 accepted as Olisthanella truncula nassonoffii (Graff, 1882) Luther, 1904
• Mesostoma nassonoffii Graff, 1882 accepted as Olisthanella nassonoffii (Graff, 1882) Luther, 1904 accepted as Olisthanella truncula nassonoffii (Graff, 1882) Luther, 1904
• Mesostoma neopolitanum Graff, 1882 accepted as Paramesostoma neapolitanum (Graff, 1882) Attems, 1896
• Mesostoma nigrirostrum Braun, 1885
• Mesostoma normatum (uncertain > unassessed)
• Mesostoma obtusum Schultze, 1851 accepted as Olisthanella obtusa (Schultze, 1851) Luther, 1904