Extracted from the California Dept of FIsh and Wildlife:
The golden trout is the State Freshwater Fish of California and has long been recognized for its unparalleled beauty. Its coloration is spectacularly bright: the belly, opercula, lower jaws, and lateral line are a vivid red to red-orange. The back is a deep olive-green, fading to bright gold on the sides of the fish. About ten parr marks are centered on the lateral line and are usually present through adulthood. Body spots (usually not present below the lateral line) are large, round, dark, and concentrated near the caudal peduncle and on the dorsal and caudal fins. Paired fins are orange, and some have white or yellow tips preceded by a black band. The dorsal fin also has a white to orange tip.
California golden trout have been widely distributed outside their native range, mostly in high elevation lakes and streams in the Sierra Nevada. They were also transplanted to numerous lakes in the Wind River Range in Wyoming.