Poecilia petenensis, the Petén molly, is a poeciliid fish species endemic to Guatemala.

Petén molly
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cyprinodontiformes
Family: Poeciliidae
Genus: Poecilia
Species:
P. petenensis
Binomial name
Poecilia petenensis
Günther, 1866

Taxonomy edit

The Petén molly is a short-finned molly (part of the Poecilia sphenops complex) whose scientific name is a matter of some confusion. It was originally described by Günther (1866), who named it Poecilia petenensis. Günther (1866) also described the swordtail molly under the name Mollienesia petenensis. Regan (1913) placed both mollies in the genus Mollienesia, renaming the short-finned species Mollienesia gracilis.[2]

When Rosen and Bailey (1963) revised the poeciliids, they placed both the swordtail and the short-finned molly in the genus Poecilia and made the short-finned species a synonym for Poecilia sphenops. Poeser (2002) revalidated Poecilia petenensis as a separate species, leading to homonymity with the swordtail species, which was duly renamed Poecilia kykesis.[2]

Meyer et al. hold that Poeser (2002) broke nomenclature codes. They argue that the designation Poecilia petenensis should continue to refer to the swordtail molly and that the short-finned molly should instead be named Poecilia gracilis.[3]

Naming history[2]
Common name Günther (1866) Regan (1913) Hubbs (1935) Rosen & Bailey (1963) Brett & Turner (1983) Poeser (2002)
Petén molly Poecilia petenensis Mollienesia gracilis Mollienesia sphenops gracilis Poecilia sphenops Poecilia "gracilis" Poecilia petenensis
Swordtail molly Mollienesia petenensis unchanged unchanged Poecilia petenensis unchanged Poecilia kykesis

Description edit

The largest examined Poecilia petenensis female measured 119 mm in standard length, while the largest males attained 93 mm. The body is relatively slender, more so than in the otherwise similar species P. teresae, and somewhat higher in the males than in the females. The sides of the fish are spotted, which is more pronounced in females. Larger females exhibit a diamond pattern on their sides. The fins are mostly without pigment.[2]

Distribution edit

Poecilia petenensis is endemic to the freshwater Lake Petén Itzá in Guatemala.[2]

References edit

  1. ^ Lyons, T.J. (2020). "Poecilia petenensis". The IUCN Red List of Threatened Species. 2020: e.T191752A165014985. doi:10.2305/IUCN.UK.2020-2.RLTS.T191752A165014985.en. Retrieved 22 August 2023.
  2. ^ a b c d e Poeser, Fred N. (2002). "Poecilia kykesis nom. nov., a new name for Mollienesia petenensis Günther, 1866, and redescription, revalidation and the designation of a lectotype for Poecilia petenensis Günther, 1866 (Teleostei: Poeciliidae)". Contributions to Zoology. 70 (4): 243–246. doi:10.1163/18759866-07004005. Retrieved 20 August 2023.
  3. ^ Meyer, Manfred K.; Schneider, Klaus; Radda, Alfred C.; Wilde, Brigitta; Schartl, Manfred (2005), "A new species of Poecilia, subgenus Mollienesia, from upper río Cahabón system, Guatemala, with remarks on the Nomenclature of Mollienesia petenensis Günther, 1866 (Teleostei: Cyprinodontiformes: Poeciliidae)" (PDF), Zoologische Abhandlungen, Dresden, retrieved 20 August 2023