Agaricus moelleri

Agaricus moelleri
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Agaricales
Family:	Agaricaceae
Genus:	Agaricus
Species:	A. moelleri
Binomial name
Agaricus moelleri Wasser (1976)
Synonyms
Agaricus placomyces Peck (1878) Agaricus meleagris Imbach (1946) Agaricus praeclaresquamosus Freeman (1979)

Agaricus moelleri Mycological characteristics
	Gills on hymenium
	Cap is flat
	Hymenium is free
	Stipe has a ring
	Spore print is brown
	Ecology is saprotrophic
	Edibility is poisonous

Agaricus moelleri, commonly known as the flat-top agaricus,^[1] inky mushroom,^[2] or dark scaled mushroom,^[3] is a large mushroom of the genus Agaricus.^[3] It appears occasionally in most kinds of woodland, during late summer, in northern temperate zones.

Taxonomy

For many years Agaricus moelleri was erroneously accredited with the binomial Agaricus placomyces by some British authors. The epithet placomyces was in fact given to a North American species of Agaricus by Charles Horton Peck in 1878 (now known as Agaricus praeclaresquamosus A.E.Freeman 1979).^[4] The current binomial Agaricus moelleri was published in 1976 by the Ukrainian mycologist Solomon P. Wasser.^[5]

Description

The cap has a greyish-brown patch in the centre and cold grey-brown scaling on the surrounding off-white background. It is 5 to 9 centimetres (2 to 3+1⁄2 in) in diameter, and yellows when bruised. It is ovate when young, flattening later.^[2] The stem has a drooping ring, and stains yellow very easily when bruised, this colour then changes to brown over time. The stem flesh bruises yellow only faintly, and is more noticeable in the base. The gills are crowded, and free, as is typical for an Agaricus. They are pink on young specimens, but brown to black on older fruit bodies. The flesh is white and does not change colour on cutting. It is noted by some authors as smelling like ink, iodoform, sweat, or mouldy straw. The spores are 4–6 x 3–4 μm, and are elliptical. The odour resembles phenol.^[6]

A similar species occurring in North America, Agaricus praeclaresquamosus A.E. Freeman 1979, has several variants, some of which are larger.^[7]

The rare Agaricus phaeolepidotus also has the iodoform, or ink smell, but has browner cap scales, and stains yellow less readily.^[3]

Distribution and habitat

Agaricus moelleri is found in the temperate zones of the northern hemisphere. North America, Asia^[8] Britain, and Europe, growing in mixed forests and woods. It is widespread, but can be locally rare, and favors rich alkaline woodland, or parkland.^[3]

Toxicity

In the same fashion as the yellow stainer (Agaricus xanthodermus), Agaricus moelleri can produce gastrointestinal symptoms for some people but not others, when ingested.^[3] It is considered toxic.^[6]

Similar species

Agaricus hondensis is similar, with a pinkish tint and firmer flesh.^[6]

See also

• List of Agaricus species

References

1. Arora, David (1986). Mushrooms demystified: a comprehensive guide to the fleshy fungi (Second ed.). Berkeley: Ten Speed Press. ISBN 978-0-89815-169-5.
2. Roger Phillips (2006). Mushrooms. Pan MacMillan. ISBN 0-330-44237-6.
3. Thomas Laessoe (1998). Mushrooms (flexi bound). Dorling Kindersley. ISBN 0-7513-1070-0.
4. "Basidiomycota Checklist-Online - Species Page". 2011-07-20. Archived from the original on 2011-07-20. Retrieved 2021-10-13.
5. Wasser SP. (1976). "Species nova e genere Agaricus L. ex Fr. emnd. Karst". Novosti Sistematiki Nizshikh Rastenii. 13: 77–9.
6. Trudell, Steve; Ammirati, Joe (2009). Mushrooms of the Pacific Northwest. Timber Press Field Guides. Portland, OR: Timber Press. pp. 190–191. ISBN 978-0-88192-935-5.
7. David Arora (1986). Mushrooms Demystified. Ten Speed Press. ISBN 0-89815-169-4.
8. Asef M.R. (2020). Field guide of Mushrooms of Iran. Tehran: Iran-Shanasi Press. p. 360. ISBN 9786008351429.

External links

• English Country Garden