Mycol. eur. 2: 166. 1822.
Common Name: black jelly drops
Synonym: Phaeobulgaria inquinans (Persoon) Nannfeldt
Fruiting body sessile to substipitate 1.0-4.0 cm broad, at first subglobose to urn-shaped, becoming turbinate, shallowly cupulate above, narrowed below; margin strongly incurved in youth, often distorted from adjacent fruiting bodies, eventually upright with a narrow lip; hymenium shallowly concave, occasionally convex, blackish-brown, smooth, shiny when wet, otherwise dull; outer surface scurfy, dingy-brown; context gelatinous, brown; odor not distinctive; taste not tried.
Spores 10.0-16.0 x 6.0-7.0 µm, smooth, thin-walled, elliptical to bean-shaped; often only the upper four spores fully developed, i.e. pigmented brown, the lower spores hyaline; asci uniseriate, apical pore bluing in Melzers reagent; spores dark-brown in deposit.
Solitary to clustered on hardwood logs in coastal forests; possibly also present at low elevations of the Sierra Nevada; fruiting throughout the mushroom season; locally common.
Commonly known as Black Jelly drops, the gelatinous, top-shaped fruiting bodies of Bulgaria inquinans are often found in large groups on downed logs of coast live oak (Quercus agrifolia) and tanbark oak (Lithocarpus densiflorus). It is most easily recognized after periods of rain, when the shallow black cups have a glossy sheen, in sharp contrast to the scurfy, brown exterior. Only Urnula padeniana and Psuedosarcosoma latahense are similar. These Ascomycete cousins are also black, rubbery, and cupulate, but differ in having a wrinkled, not scurfy exterior. Additionally, they fruit singly or in small numbers on small branches, never in large groups on logs. Unrelated to Bulgaria inquinans is the Basidiomycete jelly fungus Exidia glandulosa. It mimics Bulgaria inquinans with black, gelatinous fruitings on rotting hardwoods, but these are cerebriform, not cupulate.
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