Ebony Cup

Ebony Cup is a small, striking black disc fungus of spring conifer woodland. Each fruiting body is a shallow cup 1–3 cm across, jet black to very dark brown inside and out, with a finely felted or downy exterior and either no stalk or a very short one. They usually appear in loose troops among mosses and fallen needles, standing out sharply against the green.

Pseudoplectania belongs to the Sarcosomataceae, the family of dark, tough-fleshed Pezizales that also contains Urnula and Sarcosoma. Members are recognised by their blackish pigmentation, rubbery-elastic flesh and habit of fruiting early in the year.

Black cup fungi are few enough that the combination of colour, season, small size and conifer litter habitat identifies this species to genus with reasonable confidence in the field.

Fruiting body

A shallow to moderately deep cup 1–3 cm across (occasionally to 4 cm), at first almost closed and hemispherical, expanding to a saucer or shallow bowl, sometimes becoming irregular or wavy with age. It is sessile or has a very short, thick, tapering stalk-like base often buried in moss.

Inner surface

Smooth, matt to slightly shining, jet black to very dark brownish black, without pattern or zoning.

Outer surface

Dark blackish brown and covered in a fine felt of short dark hairs, giving a matt, minutely velvety texture; moss fragments and needle debris usually cling to the base. The margin is often slightly incurved and a little paler.

Flesh and spore print

The flesh is thin but tough and rubbery-elastic, dark grey to blackish, bending rather than snapping and not brittle like a Peziza. There is no colour change on cutting. Spores are colourless and distinctly spherical, an unusual shape among cup fungi; a spore deposit is white despite the black fruiting body.

It fruits on the floor of coniferous and mixed woodland, among mosses, needle litter, and on well-rotted buried conifer wood and twigs. Spruce, fir and pine stands, particularly cool, damp, mossy ones and upland or montane forests, are its usual setting, and it often grows where the moss layer is thick and continuous.

The season is early — early spring through to early summer, sometimes appearing near retreating snow in mountain areas, and running from March to June in most of its range. It is widespread across temperate and boreal Europe, North America and Asia, but generally recorded infrequently because of its small size and dark colour against dark litter.

Pseudoplectania nigrella is saprotrophic, decomposing conifer needle litter, moss remains and small buried woody fragments in the humus layer. Its mycelium binds together the fine organic debris of the forest floor, and fruiting bodies are often anchored in a mat of moss stems and needles.

As with other early-fruiting Sarcosomataceae, the tough, gelatinised-rubbery flesh is an adaptation to fruiting in a season of frosts and fluctuating moisture: the cups tolerate freezing and drying and resume spore discharge when conditions improve. Spores are ejected from operculate asci during mild, humid spells.

Pseudoplectania melaena (also treated as P. vogesiaca) is very similar but tends to grow directly on rotten conifer wood, is often slightly larger and has a more distinct stalk. Plectania melastoma is separated by conspicuous orange to reddish granules scattered over its dark outer surface, and Plectania nannfeldtii by a long, slender, wiry black stalk and a habit of fruiting near melting snow.

Urnula craterium is far larger, distinctly goblet-shaped with a ragged toothed mouth and grows on buried hardwood rather than conifer litter. Blackened old Peziza cups are brittle and snap when bent, lack the felted hairy exterior, and never have the rubbery elasticity of Pseudoplectania.