Shaggy Scarlet Cup Identification Guide

The find, and the scale of it

This is a species you find by kneeling down. The setting is a damp hardwood ravine, a shaded creek bank or a moist bottomland slope in spring, with a deep layer of leaf litter over rotting sticks. What you notice first is a scatter of small scarlet dots on the litter, each no bigger than a shirt button. Get low and they resolve into deep red goblets held up on slender pale stalks, several often rising together from a single buried twig. Against wet brown leaves, the colour is startling, and the second thing you register is that each cup appears to be wearing a white fur collar. That combination of intense scarlet interior and shaggy white exterior is the whole identification in one image.

Reading the cup

The fertile body is small, generally 0.5 to 1.5 cm across the mouth and often as deep as it is wide, so the profile is a narrow goblet or urn rather than a shallow saucer. Young specimens are almost closed, opening from a tight bud into a deep cup and finally into a flared bowl with a lobed or split rim.

The inner surface is the spore-bearing layer. It is smooth, matt to faintly waxy, and coloured a saturated scarlet to rose red, deepest in fresh specimens and fading towards salmon or orange-pink in sun-bleached or old ones. Because the cup is deep, the true colour is best judged by tilting it towards the light rather than looking straight down into shadow.

The outer surface is entirely different in character: whitish to pale pink and clothed in a dense coat of matted white hairs. At the rim these hairs gather into conspicuous tufts that project beyond the edge, giving the fringed, shaggy appearance the English name refers to. On very young buds the tufts can interlock across the mouth, which is why unopened specimens look like tiny white-woolly balls with a red spot.

Stalk and base

Every mature specimen has a distinct stalk, which is important. It is slender, 1 to 4 cm long and only a millimetre or two thick, whitish to pale pink, often curved, and finely downy rather than shaggy along most of its length. Follow it downwards through the litter with your fingertips: it does not end in soil but runs to a buried stick, branch fragment or root, where several stalks may spring from a common attachment point. Excavating a small area gently and photographing the whole group attached to the wood is worth doing, because the substrate is part of the identification.

Flesh and colour change

The flesh is very thin, brittle and pale, and squashes easily. There is no colour change on handling, no bleeding of any liquid and no bruising reaction. Cut a cup vertically with a razor blade and the section shows a thin red hymenial layer over pale tissue with a hairy skin outside. Nothing about the interior is fibrous or tough; this is a delicate structure that will shrivel to a hard red flake within a day of being taken out of humid conditions.

Spores, and why a standard print does not apply

This is a cup fungus, not a gilled mushroom, so the usual method of laying a cap on paper does not apply. Its spores are produced in cylindrical sacs lining the inner surface and are shot upwards into the air rather than dropped downwards.

There are still two useful field observations. First, breathe gently and warmly onto a mature cup or tap it in still, sunlit air; a faint puff of spores may be released as many sacs discharge at once, which itself confirms the group. Second, if you want a deposit, invert a cup over a slide or a piece of dark card in a humid closed box for a few hours; the discharge collects as a faint whitish film. Under a microscope the spores are large, smooth-walled, colourless and broadly ellipsoid, eight to a sac, which distinguishes the family from the small-spored disc fungi.

Substrate and season

Shaggy Scarlet Cup fruits on dead hardwood that is buried or lying in contact with damp ground: sticks, branch fragments and small logs, frequently oak, under a litter layer. It is a decomposer of that wood rather than a partner of any living plant. Moist, sheltered, shaded ground matters enormously, so ravines, stream sides, seepage slopes and north-facing bottomlands are the productive places, while dry ridges rarely produce it.

The season is spring into early summer, appearing as the leaf litter warms and stays damp, and it is one of the small red spring cups that overlap in timing with the last of the winter scarlet cups. Fruiting is often gregarious, with dozens of cups over a square metre where a single stick is colonised.

Separating it from look-alikes on structure

The scarlet cups of the genus Sarcoscypha, including Sarcoscypha coccinea, austriaca and dudleyi, are the obvious confusion. They are much larger, commonly 2 to 5 cm across, sit on very short thick stalks or almost directly on the wood, and their outer surface is whitish and finely downy but never carries the coarse projecting white tufts at the rim. They also appear earlier, through late winter and early spring, on fallen sticks that are usually exposed rather than buried.

Sarcoscypha occidentalis is a closer match in size and has a long slender white stalk, so it is the most likely mistake. Separate it on the exterior: its outer surface is smooth to very finely downy and lacks the shaggy hair coat and fringed rim entirely, its cup is shallower and more saucer-like when open, and it fruits in summer during humid spells rather than in spring.

Microstoma protractum is the nearest relative, with a longer stalk and a more elongated urn shape, but its exterior is far less hairy and it does not develop the bold white marginal tufts.

The eyelash cups, Scutellinia species, are flat orange discs sitting directly on damp wood or soil with no stalk at all, and their marginal hairs are stiff, dark brown to black and clearly separate bristles rather than white woolly tufts.

Aleuria aurantia is far larger, bright orange, wavy and stalkless on bare soil, so size and the absence of a stalk settle it at once.

Any small red cup sitting flush on exposed wood with no stalk at all, whatever its marginal hairs, is not this species: the slender stalk is obligatory here.

Field summary

Tiny deep scarlet goblet, white woolly exterior, conspicuous white tufts fringing the rim, slender pale stalk running down to buried hardwood, spring, damp shaded ravine litter, gregarious. Any specimen failing the fringed-rim test belongs somewhere else.