Chroogomphus rutilus, commonly known as the Copper Spike, is a medium-sized mushroom with a reddish-copper to golden-brown cap and thick, decurrent gills. It is mycorrhizal with conifers, especially pines, and is typically found in woodland and forest clearings.

Cap medium-sized, at first convex with the margin rolled inwards, later flattening and sometimes with a broad central umbo. Surface smooth, sticky when moist, shiny when dry, and varying in colour from reddish-copper to golden brown or purplish brown, often darker at the centre. Gills thick and widely spaced, running down the stem, initially pale ochre to yellowish and later becoming cinnamon to rusty brown as spores mature. Flesh yellowish to orange-brown, unchanging when cut. Stem cylindrical or slightly swollen at the base, smooth or finely fibrillose, coloured like the cap or paler towards the base. Spore print very dark smoky-olive to black.

Microscopic Features: Spores large and bolete-like, subfusiform in shape, measuring 15–22 × 5.5–7 µm.

Note: Chroogomphus rutilus as traditionally known in North America is now recognised as a different species. Molecular studies have shown that the true C. rutilus is confined to Europe, while North American collections previously assigned to this name are genetically identical with Chroogomphus ochraceus.

Chroogomphus rutilus on the www.first-nature.com web site.
Chroogomphus ochraceus ("rutilus") on the MushroomExpert.Com Web site.