The Tacoma pocket gopher (Thomomys mazama tacomensis) was a subspecies of the Mazama pocket gopher that was restricted to a few isolated populations in the southern Puget Sound area and on the Olympic Peninsula in Washington. The first specimen was collected in 1853 by Suckley and Cooper at Fort Steilacoom, but it was only officially described in 1919 by Taylor. Its range is believed to have covered an area from Point Defiance in Tacoma, south to Steilacoom, and east to Puyallup. Another subspecies from Washington, T. m. louiei, has been presumed extinct; however, this is less certain. Its face is a blackish color, extending to a 1-centimeter square area behind the ears.