Original description as Mollienesia petenensis:
ZooBank:4496B689-DE1E-4014-8565-477995E3393B.
- Günther, Albert C. L. G. 1866. "Catalogue of the Physostomi, containing the families Salmonidae, Percopsidae, Galaxidae, Mormyridae, Gymnarchidae, Esocidae, Umbridae, Scombresocidae, Cyprinodontidae, in the collection of the British Museum". Catalogue of the fishes in the British Museum. 6:1-368 (ffm04521)
Synonyms (1):
- Mollienesia gracilis Regan, 1913, with type locality at Lake Petén [Petén Itza], Guatemala. Determiner: Rosen & Bailey, 1963
Conservation: Poecilia petenensis is evaluated by the international union for the conservation of nature in the iucn red list of threatened species as (DD) data deficient (2020).