Girardinus metallicus

Last updated

Girardinus metallicus
Girardinus metallicus (metal girardinus) (cropped).jpg
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cyprinodontiformes
Family: Poeciliidae
Genus: Girardinus
Species:
G. metallicus
Binomial name
Girardinus metallicus
(Poey, 1854)
Synonyms

Girardinus metallicus, sometimes known as the metallic topminnow or metallic livebearer, is a species of fish from the family of the Poeciliidae.

G. metallicus females grow to 7.9 cm in standard length, while males reach 4.5 cm. [2] [3] The species is polymorphics: some males are colorless, while others have pronounced black or yellow coloring on their undersides. [4] All three morphs occur together in nature. [5]

The species is endemic to Cuba, inhabiting both the main island [6] and the Isla de la Juventud. [5] It is common in lowland swamps, lagoons, and flooded savannahs on the main island and in the Itabo River on the Isla de la Juventud. [1] Water tends to be clear and stagnant. [2] It favors sunlit areas where algae grow. [7] It feeds chiefly on detritus, algae, and mud, but occasionally also takes insect larvae and small fish. [2] [5]

Girardinus metallicus was initially thought to rely exclusively on coerced mating to reproduce; this is the only sexual behavior known in the colorless and yellow morphs. In the black morph, males perform courtship display before inserting their gonopodium (fin modified into sex appendage) into the female's genital opening. Although long gonopodia usually arise in poeciliid species that skip courtship to enforce mating, gonopodia are long in both black and yellow males, which may reflect female preference. Larger males with longer gonopodia court and try to mate more often, suggesting that black color may signal social status. Black coloration is also associated with higher aggression. The male displays by lifting his head in a "chin-up" posture, extending his gonopodium almost perpendicular to his body, and positioning himself in front of and alongside the female so that he stays within her view. [4] Broods average 13.5 offspring. Fry are born at a length of about 1 cm. They grow rapidly, reaching sexual maturity from 5 to 12 weeks old. [8]

Girardinus metallicus appears in ornamental fish trade. [9] The species was imported in Germany in 1906. [10] It is not collected in the wild. [1]

References

  1. 1 2 3 Lyons, T.J.; Ponce de León, J.; Rodríguez-Machado, S. (2021). "Girardinus metallicus". IUCN Red List of Threatened Species . 2021 e.T125977055A125986528. doi: 10.2305/IUCN.UK.2021-1.RLTS.T125977055A125986528.en . Retrieved 18 November 2021.
  2. 1 2 3 Lee, D. S.; Platania, S. P.; Burgess, G. H. (1983). Atlas of North American freshwater fishes, 1983 supplement.
  3. ↑ Lucinda, P. H. F. (2003). "Poeciliidae (Livebearers)". In Reis, R. E.; Kullander, S. O.; Ferraris, C. J., Jr. (eds.). Checklist of the Freshwater Fishes of South and Central America. Porto Alegre: EDIPUCRS. pp. 555–581.{{cite book}}: CS1 maint: multiple names: editors list (link)
  4. 1 2 Kolluru, Gita R.; Bertram, Susan M.; Chin, Eric H.; Dunmeyer, Catalina V.; Graves, Jennifer S. (2014). "Mating behavior and its morphological correlates in two color morphs of Girardinus metallicus (Pisces: Poeciliidae), a species previously thought not to exhibit courtship display". Behavioural Processes. 106. Elsevier BV: 44–52. doi:10.1016/j.beproc.2014.04.007. ISSN   0376-6357.
  5. 1 2 3 Ponce de León, J. L.; Rodríguez, R. (2010). Peces cubanos: De la familia Poeciliidae (in Spanish). La Habana: Universidad de La Habana.
  6. ↑ Reis, Roberto E. (2003). Check List of the Freshwater Fishes of South and Central America. EDIPUCRS. p. 561. ISBN   978-85-7430-361-1 . Retrieved 27 December 2025.
  7. ↑ Ponce de León, José L.; Rodríguez, Rodet; León, Gunnary (2013). "Life‐History Patterns of Cuban Poeciliid Fishes (Teleostei: Cyprinodontiformes)". Zoo Biology. 32 (3): 251–256. doi:10.1002/zoo.21009. ISSN   0733-3188 . Retrieved 1 January 2026.
  8. ↑ Ponce de León, José L.; Rodríguez, Rodet; Acosta, Martín; Uribe, Mari C. (2011). "Egg size and its relationship with fecundity, newborn length and female size in Cuban poeciliid fishes (Teleostei: Cyprinodontiformes)". Ecology of Freshwater Fish. 20 (2): 243–250. doi:10.1111/j.1600-0633.2011.00489.x. ISSN   0906-6691 . Retrieved 1 January 2026.
  9. ↑ Gavriloaie, C.; Botha, M.; Petrescu-Mag, V. I. (2016). "Some considerations regarding the online trade of Poeciliid fishes in Romania". Poeciliid Research. 6: 25–29.
  10. ↑ Novák, Jindřich; Kalous, Lukáš; Patoka, Jiří (2020). "Modern ornamental aquaculture in Europe: early history of freshwater fish imports". Reviews in Aquaculture. 12 (4): 2042–2060. doi:10.1111/raq.12421. ISSN   1753-5123 . Retrieved 2 January 2026.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.