The Coulee chipmunk (Neotamias grisescens) is a species of chipmunk native to the Channeled Scablands in central Washington. It was formerly considered a subspecies of Neotamias minimus. It is sympatric with both N. minimus and N. amoenus; it can be differentiated by these species due to its overall grayer coloration.
Description It resembles Neotamias minimus pictus, but is smaller, particularly on the hind feet. It's also a grayer and less yellow color, with the dark stripes on the back being pretty narrow and the middle pair of light stripes being a lot wider. The tail also tends to be grayer and paler.
Distribution It's endemic to the Channeled Scablands of Central and Eastern Washington, originally being known from the Grand Coulee in Douglas and Grant counties.
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