Hydrochus smaragdineus Fairmaire, 1879

Hydrochus angustatus bicolor Rey, 1885 syn.n.

Material studied. Lectotype (of Hydrochus angustatus bicolor Rey, 1885), male (Muséum d’Histoire Naturelle, Lyon): “ Hydrochus / bicolor Rey [male symbol] / mus. Lyon. [red handwritten label]”; “Museon Den Haag / Hydrochus [male symbol] / bicolor Rey [hdw] / det. A. L. van Berge / Henegouwen 1986”; “ lectotype. Van Berge / Henegouwen 1985 [red label, hdw]”.

Remarks. The study of the lectotype of H. angustatus bicolor revealed that its aedeagus is identical to that of H. smaragdineus Fairmaire (in the interpretation of Valladares, 1995), and thus it has to be considered a subjective junior synonym and not a subspecies of Hydrochus angustatus Germar, 1824 .