Subgenus Hydrophilus Geoffroy, 1762

Hydrophilus Geoffroy, 1762: 180 (Type species: Dytiscus piceus Linnaeus, 1758).

Hydrodema Laporte, 1840: 51 (Type species: Hydrophilus albipes Laporte, 1840).

Hydrosoma Laporte, 1840: 50 (Type species: Hydrophilus latipalpus Laporte, 1840).

Pagipherus Kuwert, 1893: 82 (Type species: Hydrophilus triangularis Say, 1823).

Stethoxus Solier, 1834: 302 (Type species: Hydrophilus ater Olivier, 1793 = Hydrophilus ensifer Brullé, 1837).