Glazed Cup

The Glazed Cup is one of the most attractive of the small soil-dwelling cup fungi, its interior a smooth, matt to slightly glossy white that looks almost enamelled against the dark brown hairy exterior. The cups are hemispherical to deeply bowl-shaped, 1–3 cm across, with the bristly hairs projecting beyond the rim as a shaggy fringe.

Humaria sits in the Pyronemataceae within the Pezizales, in the same broad group as Scutellinia and Geopora. Where Scutellinia pairs hairs with a brilliantly coloured disc, Humaria combines them with a pure white one — the contrast is the whole identity of the genus in the field.

Unlike many small cup fungi that need microscopy, this one is confidently named from a photograph, which makes it a favourite among woodland naturalists.

Fruiting body

A deep hemispherical to bowl-shaped cup 1–3 cm across and almost as deep, sessile or with only a rudimentary base, sometimes remaining nearly globular when young with the mouth partly closed. With age the cup widens and the margin may become slightly irregular or torn.

Inner surface

Smooth, even and white to pale greyish-white or faintly cream, sometimes with a very slight bluish or glaucous cast, matt to weakly shining. It stays pale as the fungus ages rather than darkening.

Outer surface and margin

Dark brown, densely clothed in stiff, pointed brown hairs that are longest at the rim, where they project past the margin to form an obvious shaggy fringe visible without a lens. Soil and moss fragments frequently cling to the hairs.

Flesh and spore print

The flesh is thin, whitish and brittle, breaking cleanly with no colour change. A spore deposit is white; the spores are colourless, elliptical, warted, and typically contain two conspicuous oil droplets. Fruiting is singly or in small scattered groups.

It grows on damp, humus-rich soil in broadleaved and mixed woodland, along shaded path edges, on mossy banks, and directly on very rotten wood, buried sticks, sawdust and woodchip. It has a preference for sites with a stable moist litter layer and is often found among mosses at the base of trees or on the sides of old stumps.

Fruiting runs from early summer into late autumn, with the main flush in the humid weeks of late summer. The species is widespread and locally common throughout temperate Europe, North America and Asia, and is one of the more frequently recorded of the medium-sized soil cups.

Humaria hemisphaerica is generally regarded as saprotrophic, decomposing woody debris and humus in the litter layer, although the genus has been suggested to have some capacity for root association, and its role may not be purely saprotrophic in all situations. It thrives where fine woody fragments are mixed into moist soil, which is why woodchip paths and old stump bases are such reliable sites.

The dense covering of stiff hairs is thought to help anchor the cup, shed rain and reduce desiccation of the exposed fertile surface. Spores are shot from operculate asci into air currents moving across the woodland floor, and a ripe cup will release a visible puff of spores if breathed on.

Tarzetta cupularis and T. catinus are similar-sized pale cups on woodland soil but are buff to greyish-tan inside rather than white, and their margins are finely toothed rather than fringed with long brown hairs. Geopora species share a brown-hairy exterior but develop underground and split open into star-like rays, with much of the cup remaining buried.

Trichophaea species are smaller, greyish-white cups with even longer, more conspicuous marginal hairs, often on burnt ground. Peziza species may be similarly sized but are smooth outside, lacking any hair covering, and are usually brown, ochre or violet inside rather than clean white.