Bonytail chub | |
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Bonytail chub, Gila elegans | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Cypriniformes |
Family: | Cyprinidae |
Genus: | Gila |
Species: | G. elegans |
Binomial name | |
Gila elegans S. F. Baird & Girard, 1853 |
The bonytail chub or bonytail (Gila elegans) is a cyprinid freshwater fish native to the Colorado River basin of Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming in the southwestern United States; it has been extirpated from the part of the basin in Mexico. It was once abundant and widespread in the basin, its numbers and range have declined to the point where it has been listed as endangered since 1980 (ESA) and 1986 (IUCN), a fate shared by the other large Colorado basin endemic fish species like the Colorado pikeminnow, humpback chub, and razorback sucker. It is now the rarest of the endemic big-river fishes of the Colorado River. There are 20 species in the genus Gila, seven of which are found in Arizona.
A bonytail chub can grow to 62 cm (2.03 ft) long. Like many other desert fishes, its coloring tends to be darker above and lighter below, serving as a camouflage. Breeding males have red fin bases. They have a streamlined body and a terminal mouth. Bonytail chubs have bodies that sometimes arch into a smooth, predorsal hump (in adults). While their skull is quite concave, their caudal peduncle (tailside) is thin, and almost looks like a pencil (hence, “bony tail”). The coloration of bonytail chubs is usually dark dorsally and lighter ventrally, however, in very clear waters, they looks almost black all over. During breeding season, males and females have distinct coloration as well. Mature males have bright red-orange lateral bands between their paired fins; while females have a more subdued coloration that is described with the males.