Considerado un sinónimo menor 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)
Descripción original como Gambusia myersi:
- Ahl, Ernst. 1923. "Gambusia modesta sp. n". Blätter für Aquarien- und Terrarien-Kunde. Stuttgart. 34:220-221 (ffm04572)