About this fungus
Coccora is a fungus in the Amanitaceae family. Its habitat and field characteristics are summarised below.
A large western North American Amanita with a golden-yellow, orange-brown or bronze-brown cap. One or a few thick white patches usually remain on top like pieces of a skullcap, while the cap edge is conspicuously lined. Mature fruit bodies have white to pale cream gills, a skirt-like ring high on the stem and a thick white sac at the base. The combination can be striking, but each structure needs to be seen clearly.
What to check
Excavate the complete stem base before assessing the mushroom. The volva should form a thick, loose, sack-like cup around a base that is not strongly bulbous. Look for a thick white veil patch on the cap, clear grooves around the cap margin, free or narrowly attached pale gills, a cream to pale-yellow skirt-like ring high on the stem and a white spore print. The stem is white to pale yellow and stuffed with cottony tissue when young, becoming hollow. Smooth inamyloid spores and clamp connections at the basidia support the identification microscopically. A missing cap patch or damaged ring does not prove another species, so all available characters and every specimen in a group must be checked.
Variation
Typical autumn fruit bodies are golden-brown, orange-brown or yellow-brown, often paler and more yellow near the margin. Dark-brown collections occur and wholly white examples are rare. Gills, stem and ring may be ivory-white, cream or pale yellow. Rain or soil can damage the cap patch, and the basal sac may crumble. An unopened egg looks quite different from a mature mushroom and conceals most useful characters. The pale spring coccora is not merely a colour form: DNA and morphology established it as the separate species Amanita vernicoccora in 2011.
Lookalikes
Amanita vernicoccora fruits in spring, is usually pale yellow to nearly white, often smells of fish and has a weaker, less membranous ring. Amanita velosa also fruits in spring and lacks a ring. The critical dangerous comparisons in coastal California are Death Cap, Amanita phalloides, and Western Destroying Angel, Amanita ocreata. Both can have white gills, a ring and a basal sac, and both contain amatoxins that can cause liver failure and death. Death Cap usually lacks the thick white cap patch and strongly lined margin and has a bulbous base inside a thinner sac; Western Destroying Angel is white to ochre and mainly a spring mushroom. Weather, age and damage can blur these distinctions, and an Amanita egg provides too little visible evidence for a dependable field identification.
Habitat and range
Mycorrhizal in the Pacific coastal region of western North America. In Washington, British Columbia and northern Oregon it is strongly associated with Douglas-fir. Farther south in Oregon and northern California it is particularly associated with Pacific madrone, with live oak also documented in the San Francisco Bay area. It fruits alone, scattered or in groups after the autumn rains and through winter. Reports of a pale spring coccora should be assessed as Amanita vernicoccora rather than extending this species automatically into spring.
Food safety
Edible, with caution.
Use this profile to learn what to examine and compare, not as proof that a mushroom is safe to eat. Check the whole specimen and every important lookalike before reaching an identification.
Photographs
Alan Rockefeller / CC BY-SA 4.0