 Genetically it cannot be distinguished from the Yellowstone cutthroat trout, and before the construction of dams there were no physical barriers between the ranges of the two subspecies in the Snake river drainage.The subspecies was scientifically named in 1995 in a popular book by the columnist M. R. Montgomery, to honor the fisheries research of Dr. Robert J. Behnke, who had presented its (unnamed) description in 1992.While fine-spotted x rainbow trout crosses are observed in the South Fork of the Snake River in Idaho, they are infrequently encountered and appear to be hatchery hybrids.