Peziza vesiculosa

Sporocarp
Fruiting body 2-5 cm broad, sessile, globose, becoming urn-shaped, often contorted when clustered; margin incurved, remaining so in age, at times eroded or cracked in age; hymenium (inner surface) light-brown, pale yellow-brown to medium brown, frequently convoluted or wrinkled; outer surface granulose to furfuraceous, sometimes indistinctly so when weathered, tan, pale-buff, to nearly white; flesh thin, pale yellow-brown, fragile; odor and taste mild.

Spores
Spores 20-24 x 11-13 µm, elliptical, smooth, lacking oil droplets; white in deposit.

Habitat
Scattered to clustered on manure (especially horse manure), and composted straw; common around stables and horse pastures; fruiting fall, winter and spring.

Edibility
Unknown.

Comments
A combination of characters make this Peziza relatively easy to identify. Most obvious is its preference for fruiting in clusters on horse dung or decayed straw. While many other cup fungi also occur on dung, in our area all are smaller, differently colored, or have hairs on the cup margin. Peziza vesiculosa is additionally distinguished by an urn-shaped cup with a margin incurved even at maturity, a wrinkled yellowish-brown hymenial inner surface and a pale tan furfuraceous outer surface.