Erstbeschreibung als Xiphophorus pygmaeus:
ZooBank:7EA07A04-488D-4853-A1C1-EC49B65A595A.
- Hubbs, Carl Leavitt & M. Gordon. 1943. "Studies of cyprinodont fishes. XIX. Xiphophorus pygmaeus, new species from Mexico". Copeia. 1943(1):31-33 (ffm00064)
Artenschutz: Xiphophorus pygmaeus wurde durch die Internationale Union für die Erhaltung der Natur (IUZN) in der Roten Liste bedrohter Arten bewertet als (DD) Daten unzureichend (2018). Although the Huichihuayan and Axtla rivers carry enough flow and most areas remain in very good shape, with some remaining pristine areas, increasing deforestation, pesticides and fertilizers use, and pollution (particularly around Huichihuayan) are common problems that affect them and have to be resolved, particularly given human population increase in the area. During the past years, I have seen an increase in the amount of green algae in the rivers, which was rare before.