Garlic Parachute

Mycetinis alliaceus, long known as Marasmius alliaceus, is the largest of the garlic-scented litter fungi of European beech woods. The genus Mycetinis was split from Marasmius on molecular grounds and contains a small group of species united by their strong alliaceous odour.

The species is distinctive in proportion as much as in colour: a modest cap of a couple of centimetres perched on a tough, dark stem that can be five times as long, tapering into the leaf mould where it traces a buried twig or leaf skeleton. Troops of these tall, thin mushrooms rising from apparently bare beech litter are a familiar autumn sight on chalk and limestone.

The smell is released readily and often reaches the observer before the mushrooms are seen, making the species one of the few agarics that can be located by nose.

Cap

The cap is 1-3 cm across, conical to bell-shaped then convex, pale grey-brown to greyish ochre, hygrophanous and fading to buff or almost whitish as it dries, with a translucently lined margin when moist and often a slightly wrinkled surface.

Gills

Gills are whitish to pale greyish, moderately spaced, fairly broad, and narrowly attached to the stem.

Stipe

The stem is the key feature: 5-15 cm long, only 1-3 mm thick, very tough, blackish brown to almost black and covered with a fine velvety or minutely downy coating, paler at the extreme apex, and tapering downward into a rooting extension that runs into the litter to a buried twig or petiole.

Flesh, smell and spore print

Flesh is thin, tough and pliant. The smell of garlic is strong and persistent, obvious in fresh material and often still detectable in dried specimens. The spore print is white.

This species is closely tied to beech (Fagus). It fruits from buried beech twigs, leaf petioles, cupules and leaf skeletons in deep litter, most abundantly on calcareous soils, and appears in scattered troops rather than tight clusters.

The season runs from late summer into late autumn. It is widespread through beech-growing regions of Europe, occurring more locally where beech is scarce, and is essentially absent from areas without suitable host litter.

Mycetinis alliaceus is a litter saprotroph specialising in the small woody fractions of beech debris. The rooting stem base is effectively a pseudorhiza connecting the fruit body to the buried twig the mycelium is decaying, which is why pulling one up neatly extracts a scrap of blackened wood.

By attacking twigs and petioles rather than leaf blades, it occupies a slightly different niche from the leaf-decaying parachutes that share the same litter layer, and successive species in the decay sequence gradually reduce beech debris to humus.

Mycetinis scorodonius shares the garlic smell but is much smaller, with a shorter stem that is smooth, shining and reddish brown rather than velvety and blackish, and it favours twigs and grass litter rather than deep beech mould.

Marasmius wynneae grows in the same beech litter but has a whitish to lilac-tinged cap, a much shorter two-toned stem with a white woolly base, and no garlic smell. Gymnopus androsaceus has a comparably dark wiry stem but is a fraction of the size, with a hair-thin smooth stem and a cap under a centimetre. Various Mycena species share the lined cap but are brittle, paler-stemmed and lack the long rooting base.