Evolution and Systematics
Eyes of piranhas can see in dark, murky waters because they can detect far-red light.
"Thanks to far-red light, some fish can see even in water that appears black to us. The ferocious piranha, for example, swimming in the murky waters of the Amazon, perceives the water as dark red, a color that is visually penetrable, rather than black. The water looks red because the molecules of rotting vegetation in it absorb most wavelengths of visible light except far-red light, which is reflected back and can be seen by the piranha, allowing it to see the prey that it is hunting, apparently in the dark." (Shuker 2001:19)
Learn more about this functional adaptation.
- Shuker, KPN. 2001. The Hidden Powers of Animals: Uncovering the Secrets of Nature. London: Marshall Editions Ltd. 240 p.
Molecular Biology and Genetics
Statistics of barcoding coverage
Specimens with Sequences:60
Specimens with Barcodes:53
Species With Barcodes:2
Pygocentrus is a genus of the piranha family Serrasalmidae. All species are native to tropical and subtropical South America. All the species are predatory, scavengers and form huge schools. The famous red-bellied piranha, Pygocentrus nattereri, is one of four species in the genus. The Chi-Cohala[spelling?] tribe uses the teeth to make tools and weapons.
There are currently four recognized species in this genus:
- Pygocentrus cariba (Humboldt, 1821) (black spot piranha) – Orinoco river basin.
- Pygocentrus nattereri Kner, 1858 (red piranha, red-bellied piranha) – Amazon, Paraguay-Paraná-Uruguay, and Essequibo river basins, as well as various river in northeastern Brazil.
- Pygocentrus palometa Valenciennes, 1850 – Orinoco river basin, validity questionable.
- Pygocentrus piraya (G. Cuvier, 1819) (San Francisco piranha) – São Francisco River
- Fink, W. 1993. Revision of the piranha genus Pygocentrus (Teleostei, Characiformes). Copeia 3:665-687.
- Machado-Allison, A. & W. Fink. 1996. Los peces caribes de Venezuela> diagnosis, claves, aspectos ecológicos y evolutivos. Universidad Central de Venezuela, CDCH, (Colección Monografías)Caracas, 149p. ISBN 980-00-0967-1
|This Characiformes-related article is a stub. You can help Wikipedia by expanding it.|
To request an improvement, please leave a comment on the page. Thank you!