Prostoma is a genus of freshwater nemerteans, containing the following species:

• Prostoma asensoriatum Montgomery, 1896
• Prostoma canadiensis Gibson & Moore, 1978
• Prostoma communopore Senz, 1996
• Prostoma eilhardi (Montgomery, 1894)
• Prostoma graecense (Böhmig, 1892)
• Prostoma hercegovinense Tarman, 1961
• Prostoma jenningsi Gibson & Young, 1971
• Prostoma kolasai Gibson & Moore, 1976
• Prostoma ohmiense Chernyshev et al., 1998
• Prostoma puteale Beauchamp, 1932

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