The “mycena” are a large group of diminutive, delicate mushrooms. Most are a drab grey or brown, however, a few are brightly colored.
Following heavy rains, scarlet bonnet (Mycena adonis) can be found amid the needle beds of coniferous forests in Washington, Oregon and California as well as parts of Europe and China. Scarlet bonnet grows single or in small scattered groups.
The conical cap is red at first and then, beginning at the margin, fades to orange or orange-yellow. With time the cap expands and becomes more convex. The pale orange to whitish gills are adnexate (stuck to the stem at less than a right angle and curve upward to the stem) and well spaced. There are also short gills that do not extend completely from the margin to the stalk (lamellulae). The narrow stem is yellowish to whitish with a dirty yellow or brown base.
M. adonis is also known scientifically as Atheniella adonis.
Scarlet bonnet is considered toxic. Even if it were edible, it would take a large number for even a single mouthful since the fungus is so small. Better that we simply enjoy the bright flash of color this little mushroom adds to the forest floor in late fall or early spring.
These scarlet bonnets were photographed along the Falls Trail in Burney Falls State Park CA.