Lactarius pseudomucidus

It has a charcoal brown cap, smooth and slimy, from 2–10 centimetres (3⁄4–4 in) across, initially flat convex, becoming shallowly depressed. The gills are decurrent, white with a gray or yellow tinge, staining brownish.^[2] The stipe is 2.5–10 cm (1–4 in) tall and 5–12 millimetres (1⁄4–1⁄2 in) thick;^[3] it is hollow and brittle. Both the cap and stipe are mucilaginous.^[2] The flesh is gray and the latex is milky white, drying yellowish.^[2] There is only a slight odor, and the taste slowly becomes acrid. Spores are white in mass, ellipsoid, amyloid, about 8 μm long, with a reticulate decoration on the surface.^[4][5] The spore print is cream.^[3]

The species is inedible,^[6] with the extremely viscid cap and stalk being deterrent.^[1]

It resembles Lactarius argillaceifolius, which has a light orange-gray cap,^[7] and eastern North America's L. mucidus.^[2] Additionally, L. fumosus and Lactifluus gerardi bear similarities.^[3] Other Lactarius species with slippery, grayish caps are either zonate and/or the gills stain purple.^[3]

It is native to northwestern North America, often found in coastal and conifer forests.^[2]