Coprinus comatus — Shaggy mane

Card image cap

Shaggy manes2, photograph by Ludovic Le Renard.

Edible with caution

Gills: Free and very crowded, white at first, dissolving into black ink
Spore Print: Black

Left image: Shaggy manes fresh and young15, photograph by Berni van der Meer.
Right image: Shaggy manes liquefy overnight into oozing black slime, photograph by Berni van der Meer.


Odour: Spicy mushroom-like.
Cap: 2.5–7 cm in diameter and 5–20 cm tall; cylindrical with a rounded top when young, expanding when mature to flat, its margin rolling upwards to reveal liquefying, inky black gills. Cap surface white with light brown, flat scales and a solid light brown patch on the centre top. The background becomes increasingly fibrillose as the cap matures.
Gills: Very crowded, almost touching the stem. The white gill edge forms a thick protective band in the closed cap. Gill colour is initially white to cream, then changes from the cap margin inwards. First a pink blush shows, then the maturing spores colour the gills black. The gills begin to self-destruct into a black ink containing the spores.
Stem: 10–25 cm long x 1–2 cm wide, cylindrical but widened at the utmost base. The colour is white to cream, with fibres on the surface. The stem is hollow with a white cord inside that stretches from the top to the base.
Ring: A small movable ring on the stem, after the cap has expanded.
Cup: None.
Spores: 10–14 x 5.5–7.5 µm, black with a dull surface and a germ pore.
Habitat: In groups and clusters in lawns and pastures, gardens, cemeteries, along forest roads, and in other disturbed areas.
Geographical distribution: Throughout BC and the Pacific northwest, also in Alaska except for the far north. Worldwide.

Coprinopsis atramentaria, the common inky cap. Common inky caps are edible but only if alcohol is avoided. If eaten within a few days of consuming alcohol, the common inky cap causes symptoms including flushing, dizziness, headaches, and gastrointestinal upsets6. Like the shaggy mane, gill edges of the common inky cap turn black and liquefy with age. Unlike the shaggy mane, the cap is short, usually less than 8 cm tall, and it is grey to brown, smooth, without scales7.

Coprinopsis atramentaria

Common inky caps8 photograph by Ludovic Le Renard. Edible, but not if alcohol is consumed within a few days of eating them.

Chlorophyllum molybdites4, the green-gill parasol is a poisonous species common in California. As yet unknown from Oregon, Washington, and BC, it may be expanding its range to the north. Like the shaggy mane, the green-gill parasol is common in lawns and both species have a white cap with brown scales. The immature green-gill looks like a ball on a stick because its stems are long and its unexpanded caps are roughly spherical. The young shaggy mane cap is usually elongate, egg-shaped. As the cap of the green-gill parasol matures, it expands and flattens but its margin does not roll upwards and its gills do not liquefy into black ink.

It is hard to imagine a species that is more distinctive and easier to recognize than the shaggy mane.

Young shaggy manes are eaten but they need to be consumed as soon as possible after collection, before they turn black.

Because they absorb heavy metals, shaggy manes have potential uses in bioremediation of contaminated soils9,10. However, their ability to accumulate mercury and other toxic heavy metals also means that mushrooms growing from disturbed and contaminated soil should not be eaten10.

Shaggy manes have no known toxins that affect humans but like most kinds of mushrooms, they have been linked to a few incidents of illness including gastrointestinal upsets11. In some cases, illnesses attributed to shaggy manes may have been caused by misidentified common inky caps or green-gill parasols12,13.

Shaggy manes form small spiny structures in the soil, which can tear through the skin of nematodes. They also seem to have anti-nematode toxins14.

Treatment: Contact your regional Poison Control Centre if you or someone you know is ill after eating shaggy manes. Poison centres provide free, expert medical advice 24 hours a day, seven days a week. If possible, save the mushrooms or some of the leftover food containing the mushrooms to help confirm identification.

Poison Control:
British Columbia: 604-682-5050 or 1-800-567-8911.
United States (WA, OR, ID): 1-800-222-1222.

1
MyCoPortal. Mycology Collections Portal, <http://mycoportal.org/portal/collections/harvestparams.php> accessed February 2018.
2
Coprinus comatus UBC F33269.
3
Trudell, S., Ammirati, J. F. & Mello, M. Mushrooms of the Pacific Northwest. Timber Press, Portland, Oregon (2009).
4
Siegel, N. & Schwarz, C. Mushrooms of the Redwood Coast. A Comprehensive Guide to the Fungi of Coastal Northern California. Ten Speed Press, Berkeley, California (2016).
5
Uljé, C. B. Coprinus Pp. 22-119 in Flora Agaricina Neerlandica Vol. 6 (eds Noordeloos, M. E., Kuyper, T. W., & Vellinga, E. C.) Taylor & Francis, New York (2005).
6
Leikin, J. B. & Paloucek, F. P. Poisoning and Toxicology Handbook, 4th ed., CRC Press, Boca Raton, Florida (2008).
7
Arora, D. Mushrooms Demystified. Ten Speed Press, Berkeley, California (1986).
8
Specimen Coprinopsis atramentaria UBC F32055.
9
Cen, F., Chen, L., Hu, Y. J. & Xu, H. Chelator-induced bioextraction of heavy metals from artificially contaminated soil by mushroom (Coprinus comatus). Chem. Ecol. 28, 267-280, doi:10.1080/02757540.2011.644538 (2012).
10
Falandysz, J. Mercury bio-extraction by fungus Coprinus comatus: a possible bioindicator and mycoremediator of polluted soils? Environmental Science and Pollution Research 23, 7444-7451, doi:10.1007/s11356-015-5971-8 (2016).
11
Beug, M. W., Shaw, M. & Cochran, K. W. Thirty-plus years of mushroom poisoning: Summary of the approximately 2,000 reports in the NAMA case registry. McIlvainea 16, 47-68 (2006).
12
Beug, M. W. Amatoxin Mushroom Poisoning in North America 2015-2016. McIlvainea 25 (2016). <http://www.namyco.org/toxicology_reports.php>.
13
Beug, M. W. NAMA Toxicology Committee Report North American Mushroom Poisonings, <https://www.namyco.org/toxicology_committee_report_20.php> accessed May 6, 2017.
14
Luo, H. et al. Coprinus comatus damages nematode cuticles mechanically with spiny balls and produces potent toxins to immobilize nematodes. Appl. Environ. Microbiol. 73, 3916-3923, doi:10.1128/aem.02770-06 (2007).
15
Specimen Coprinus comatus UBC F29175, GenBank #MH718204.