Mexican golden trout

Mexican golden trout
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Salmoniformes
Family: Salmonidae
Genus: Oncorhynchus
Species: O. chrysogaster
Binomial name
Oncorhynchus chrysogaster
(Needham & Gard, 1964)

The Mexican golden trout (Oncorhynchus chrysogaster) is a species of fish in the Salmonidae family. It is endemic to Mexico.

Description

The Mexican golden trout is sexually dimorphic, males can easily be identified from females due to their much longer jaws or kype. Mexican golden trout are brightly colored with blue parr marks on both males and females along the side of the body. Purple scaling is visible along the lateral line. Both sexes also have bright golden-yellow belly coloration. The top of the fish and the tailfin are covered in small black spots with much larger spotting on the dorsal fin. The pectoral fins, pelvic fin and anal fin are light orange in color with white tips. Due to their harsh and small stream habitat the Mexican golden trout remains small even when fully grown. Adults rarely reach over a foot long with the maximum size probably being 10 inches (25 cm).

Distribution

Mexican golden trout have an extremely limited range, being found only in the pristine high-elevation headwaters of the Fuerte River, Sinaloa River, and Culiacán River drainages in the Sierra Madre Occidental.

Habitat

Mexican golden trout are limited to small streams known as arroyos created by small cienegas (spring-fed marshes) above 5,000 feet. The surrounding landscape is dominated by deep canyons, scrub forest, evergreens and hardwoods.

Status and threats

Due to their small range and highly sensitive, isolated habitat Mexican golden trout are considered vulnerable. The biggest threats being human development and the possibility of competition/interbreeding with hatchery rainbow trout. The Mexican golden trout was declared an endangered species in 1996.

Sources