The Umatilla dace has only recently been recognized as a separate species. It is endemic to the Columbia River system and is thought to be the product of an early Pleistocene hybridization involving leopard and speckled dace. Very little is known about its habitat requirements. There are two forms of Umatilla dace in B.C. — one in the Columbia and Slocan rivers and the other in the Similkameen River. There are subtle differences in their morphology and some evidence of molecular differentiation. The relationship between the two forms and their habitat requirements needs study.
Source: Information provided by Don McPhail for E-Fauna BC.
North America: Columbia River drainage in British Columbia (Canada), Idaho, Washington and Oregon, USA.
. Page, L.M. and B.M. Burr 1991 A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston. 432 p