provided Richardson with specimens. In 1855, William P. Gibbons, the curator of Geology and Mineralogy at the California Academy of Sciences, found a population and named it (Latin: rainbow), later corrected to . These names faded once it was determined that Walbaum's description of type specimens was conspecific and therefore had precedence. In 1989, morphological and genetic studies indicated that trout of the Pacific Basin were genetically closer to Pacific salmon (Oncorhynchus species) than to the Salmos – brown trout or Atlantic salmon of the Atlantic Basin. Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat, and other Pacific Basin trout into the genus Oncorhynchus. Walbaum's name had precedence, so the species name became the scientific name of the rainbow trout. The previous species names irideus and gairdneri were adopted as subspecies names for the coastal rainbow and Columbia River redband trout, respectively. Anadromous forms of the coastal rainbow trout or Columbia River redband trout are commonly known as steelhead. Subspecies Subspecies of are listed below as described by fisheries biologist Robert J. Behnke (2002). Description Resident freshwater rainbow trout adults average between in riverine environments, while lake-dwelling, and anadromous forms may reach . Coloration varies widely between regions and subspecies. Adult freshwater forms are generally blue-green or olive green with heavy black spotting over the length of the body. Adult fish have a broad reddish stripe along the lateral line, from gills to the tail, which is most pronounced in breeding males. The caudal fin is squarish and only mildly forked. Lake-dwelling and anadromous forms are usually more silvery in color with the reddish stripe almost completely gone. Juvenile rainbow trout display parr marks (dark vertical bars) typical of most salmonid juveniles. In some redband and golden trout forms, parr marks are typically retained into adulthood. Some coastal rainbow trout and Columbia River redband trout populations and cutbow hybrids may also display reddish or pink throat markings similar to cutthroat trout. In many regions, hatchery-bred trout can be distinguished from native trout via fin clips. Fin clipping the adipose fin is a management tool used to identify hatchery-reared fish. Life cycle Rainbow trout, including steelhead forms, generally spawn in early to late spring (January to June in the Northern Hemisphere and September to November in the Southern Hemisphere) when water temperatures reach at least . The maximum recorded lifespan for a rainbow trout is 11 years. Freshwater life cycle