Subgenus Methydrus Rey, 1885

Methydrus Rey, 1885: 253 (Type species: Hydrophilus affinis Thunberg, 1794).

Agraphilydrus Kuwert, 1888b: 280 (Type species: Hydrophilus affinis Thunberg, 1794).

Gemelus García, 2000: 223 (Type species: Gemelus pallidus García, 2000).