The Baja California rainbow trout or San Pedro Martir trout or Nelson's trout ('' Oncorhynchus mykiss nelsoni'') is a localized subspecies of the rainbow trout (''Oncorhynchus mykiss''), a

freshwater fish Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of ...

in the family

Salmonidae Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefis ...

. Baja California rainbow trout is one of many species of Mexican native trout.

Distribution

It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to headwater tributaries of the Rio Santo Domingo in the

Sierra de San Pedro Mártir Sierra de San Pedro Mártir ( Kiliwa: ʔxaal haq, en, mountains of Saint Peter the Martyr) is a mountain range located within southern Ensenada Municipality and southern Baja California state, of northwestern Mexico. It is a major mountain ran ...

mountain range of the Peninsular Ranges System, located in

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

state on the northern Baja California Peninsula.

Taxonomy

19th century

The first records of trout in northwestern Mexico were published by

paleontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

E. D. Cope in 1886 where he describes two specimens from Chihuahua as having the appearance of ''Salmo purpuratus'' a name sometimes incorrectly used for cutthroat trout (''Oncorhynchus clarki''). In 1898 and 1905, naturalist E. W. Nelson with the U.S. Biological Survey led explorations into the Mexican mainland (1898) and Baja California Peninsula (1905) to document flora and fauna.

20th century

In 1908, preserved specimens of trout that Nelson brought back from the Rio Santo Domingo (Santo Domingo creek) in the

mountains of

were described by ichthyologist B.W. Evermann as a new species ''Salmo nelsoni'', the Baja rainbow trout. In 1989, morphological and genetic studies indicated trout of the

Pacific basin The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

were genetically closer to Pacific salmon (''Oncorhynchus'' species) than to the ''

Salmo ''Salmo'' is a genus of ray-finned fish from the family Salmonidae. The single ''Salmo'' species naturally found in the Atlantic North America is the Atlantic salmon, whereas the salmon and trout of the Pacific basin belong to another genus, '' ...

''s– brown trout (''S. trutta'') or Atlantic salmon (''S. salar'') of the

Atlantic basin The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

. Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat and other Pacific basin trout, including the Mexican native trout into the genus ''Oncorhynchus''. Thus ''Salmo mykiss nelsoni'' became ''O. m. nelsoni''.

References

Oncorhynchus Trout, Baja California Endemic fauna of the Baja California Peninsula Natural history of the Peninsular Ranges Subspecies {{Salmoniformes-stub

Distribution

Taxonomy

19th century

20th century

See also

References