Kalapuya brunnea is a species of truffle in the monotypic fungal genus Kalapuya. The truffle occurs only in the Pacific Northwest region of the United States, in western Oregon and northern California. Known locally as the Oregon brown truffle, it was formerly thought to be an undescribed species of Leucangium until molecular analysis demonstrated that it was distinct from that genus. The species was first described scientifically in 2010, based on specimens collected in February 2009 from Benton County, Oregon. The truffle is reddish brown with a rough and warty outer skin, while the interior spore-producing gleba is initially whitish before developing greyish-brown mottling as it matures. Mature truffles have an odor resembling garlicky cheese, similar to mature Camembert. The species has been harvested for culinary purposes in Oregon.