Identification
The Bark Bonnet (*Phloeomana speirea*) is a master of miniaturization. To find it, you’ll need to get your knees dirty and perhaps reach for a hand lens. The cap is tiny, ranging from a mere 2 to 10 mm in diameter. It begins convex but quickly flattens, often developing a slight central depression. Its color is a subtle palette of pale grey-buff to ivory, usually darker at the center with translucent-striate lines radiating to the edge. The "smoking gun" for identification lies in the gills: unlike many of its *Mycena* lookalikes, the gills of *P. speirea* are distinctly decurrent, meaning they run slightly down the stem. The stem itself is hair-thin, translucent, and surprisingly resilient for its size.
Habitat & Range
This species is a specialist of the "vertical forest." You won’t find it in the soil; instead, look for it on the mossy bark of living deciduous trees or fallen, decaying logs. It has a particular affinity for Elder (*Sambucus*) and Maple (*Acer*). It is widespread across the temperate Northern Hemisphere, from the damp woodlands of the Pacific Northwest to the ancient forests of Europe, thriving in humid, low-elevation river valleys and shaded ravines.
Behaviour
The Bark Bonnet is an ephemeral dancer. It appears in "gregarious" groups—scattered clusters that seem to sprout overnight following heavy autumn rains. While most mushrooms vanish at the first sign of a hard frost, this hardy species can often be found fruiting well into early winter. For the wildlife photographer, they offer a stunning study in translucency when backlit by a low winter sun.
Diet
As a saprobic species, the Bark Bonnet is part of nature’s elite recycling crew. It feeds by secreting enzymes that break down complex organic polymers like lignin and cellulose within the bark and decaying wood, returning vital nutrients to the forest ecosystem.
Fascinating Fact
Despite its fragile appearance, the Bark Bonnet is a winter survivor! It possesses a remarkable ability to survive being frozen solid during a cold snap. When the ice thaws, the mushroom can often resume its spore-dropping duties as if the freeze never happened—a feat of cellular endurance that would kill most larger fungi.