Notonecta furcata var. meridionalis Poisson, 1926: 240 (upgraded to ssp. of Notonecta obliqua by Poisson, 1933: 341; upgraded to sp. by Zimmermann, 1982: 200). ST(S): "bassin méditerranéen, Afrique du Nord".
?Notonecta melanota Leach & Risso in Risso, 1826: 215 (syn. with obliqua, Kirkaldy, 1897d: 420; syn. Kanyukova, 1973a: 363, suspected). ST(S): France, Alpes Maritimes.
Notonecta glauca hybrida Poisson, 1933: 343 (syn. Kanyukova, 1973a: 363). ST(S): France, Pyrénées-Orientales; unknown (spec. in USNM, not marked as types; Froeschner, in litt.).
?Notonecta glauca kervillei Poisson, 1933: 348 (syn. Kanyukova, 1973a: 363, suspected). STS: Turkey, Smyrne [= Izmir] and Angora [= Ankara]; MNHN.
Notonecta glauca rufescens Poisson, 1933: 343 (syn. Kanyukova, 1973a: 363). ST(S): Morocco, Algeria, Tunisia, and Hungary (environs de Soroksar); unknown (spec. in USNM, not marked as types; Froeschner, in litt.).
Notonecta glauca hybrida f. tamaninii Filippi, 1949: 58. Infrasubspecific, unavailable (Kanyukova, 1973a: 363).