Marasmius siccus

Marasmius siccus, or orange pinwheel, is a species of fungus in the Marasmius genus. It is found in Eurasia and eastern North America.

Description

The small orange mushroom has an umbrella-shaped cap which is wide. The gills are whitish. The tough shiny bare stem is pale at the top but reddish brown below, and tall.

Microscopic details

At a microscopic level, the club-shaped spores are very long and thin, being roughly 19 μm by 4 μm. The distinctive cheilocystidia are broadly club-shaped with finger-like protrusions at the far end. Such cells also sometimes occur in other related mushrooms and they are known as "broom cells of the siccus type".

Similar species

M. fulvoferrugineus and M. pulcherripes are similar, but the caps are more pink.

Habitat and distribution

This mushroom is found in hardwood forests. It is distributed in northern Europe and Asia, and in North America from July to September, from the Rocky Mountains to the Appalachians.

Edibility

Although nonpoisonous, the mushrooms are too small to be considered worthwhile as food.