Clathrus ruber

Sporocarp
Fruiting body 4-7 cm broad, rounded to pulvinate; peridium thin, white, irregularly bumpy over an inner gelatinous layer; fruiting body expanding and rupturing to reveal a pale orange to reddish-orange, hollow, fragile, lattice-work structure, the inner surface lined with a sticky, fetid-odored gleba; rhizomorphs (thickened mycelium) are characteristically found at the base of fruiting bodies.

Spores
Spores 4.5-5.5 x 2-2.5 µm, olive brown, oblong, smooth.

Habitat
Solitary, scattered to gregarious in wood chips, occasionally in grass and disturbed ground; restricted to watered, urban habitats and probably an introduced species; fruiting during the warmer months of the year.

Edibility
Questionable. Some members of the stinkhorn group are edible when immature, but lacking local experience it cannot be recommended. The odor of mature specimens alone would be a major deterrent.

Comments
A spectacular and beautiful fungus, Clathrus ruber makes a remarkable transformation from a white, bumpy-surfaced, egg-stage, to a bright reddish-orange, hollow, fragile lattice-work structure. Unfortunately, the beauty of this fungus is overshadowed by its odor which is of rotting flesh. Clathrus ruber is one of a number of fungi, e.g. Psathyrella species, Hypholoma aurantiaca, Hygrophoropsis aurantiaca, which are becoming more common in the S.F. Bay Area the result of the trend of parks to grind up fallen trees into chips used for mulch in flower beds.