Considéré comme synonyme junior de Gambusia affinis (Baird & Girard, 1853)
- Baird, Spencer F. & C.F. Girard. 1853. "Descriptions of new species of fishes collected by Mr. John H. Clark, on the U. S. and Mexican Boundary Survey, under Lt. Col. Jas. D. Graham". Proceedings of the Academy of Natural Sciences of Philadelphia. 6:387-390 (ffm04562)
Décrit initialement sous Gambusia myersi:
- Ahl, Ernst. 1923. "Gambusia modesta sp. n". Blätter für Aquarien- und Terrarien-Kunde. Stuttgart. 34:220-221 (ffm04572)