Pluteus admirabilis

[ Basidiomycetes > Agaricales > Pluteaceae > Pluteus . . . ]

by Michael Kuo

For those of us who live in areas where finding a Pluteus usually means finding a boring, brown mushroom, Pluteus admirabilis is a welcome sight, quite admirably holding up the not-boring side of the genus. It is recognized as a Pluteus by its pinkish mature gills and spore print, its habitat on rotting wood, and its lack of a volva (separating it from potential confusion with Volvariella)--and among species of Pluteus, it is distinguished by its bright yellow cap and stem, and its smooth cap texture.

Pluteus admirabilis is listed as edible in field guides; I have not tried it.

Description:

Ecology: Saprobic on decaying hardwood logs and stumps; growing alone or gregariously; summer and fall; widely distributed and thoroughly documented east of the Rocky Mountains--but I have also found it at high elevation in southwest Colorado, on unidentified wood in a spruce-fir-aspen forest, and one 1962 collection labeled Pluteus admirabilis, from Utah, can be found in the online records of the National Fungus Collection (BPI).

Cap: 1-3 cm; convex becoming broadly convex to flat, sometimes with a central bump; moist; smooth; the margin lined; bright yellow when young, dull yellow or brownish yellow in age.

Gills: Free from the stem; close; whitish to pale yellowish, becoming pinkish.

Stem: 3-6 cm long; 1-3 mm thick; equal; fragile; smooth; bright yellow; basal mycelium white.

Flesh: Insubstantial; pale to yellowish.

Odor and Taste: Not distinctive.

Spore Print: Pink to salmon.

Microscopic Features: Spores 5.5-7 x 4.5-6 µ; subglobose; smooth. Pleurocystidia mostly fusoid-ventricose; to about 60 x 18 µ; cheilocystidia similar, or clavate. Pileipellis hymeniform ("cellular"), with elements 18-30 µ wide.

REFERENCES: Peck, 1872. (Saccardo, 1887; Kauffman, 1918; Singer, 1956; Homola, 1972; Smith, Smith & Weber, 1979; Phillips, 1991/2005; Lincoff, 1992; Horn, Kay & Abel, 1993; Barron, 1999; McNeil, 2006; Miller & Miller, 2006.) Herb. Kuo 07100303, 06040401, 08150709.

The European species Pluteus leoninus is similar, if not identical. Some North American authors use this name to represent a Pluteus that shares all the features of Pluteus admirabilis but has a white stem. The North American species Pluteus melleus and Pluteus chrysophlebius, if they are truly distinct, have duller yellow caps; the former has a pale yellow stem, while the latter has a white stem.

Further Online Information:

Pluteus admirabilis at Roger's Mushrooms

Pileipellis

Cystidia

The collection above, from Illinois, includes dark brown specimens that were growing alongside yellow ones in the woody debris surrounding a large dead oak. By rights the brown specimens should be something like Pluteus lutescens, since their stems are bright yellow. Curiously, however, all the brown specimens found were in the "button" stage, with caps still conical-convex, raising the (remote) possibility that they were young, brown versions of Pluteus admirabilis. Unfortunately, no "intermediate" specimens were found to prove or disprove the idea, though completely yellow buttons were also found.

© MushroomExpert.Com

Cite this page as:

Kuo, M. (2004, December). Pluteus admirabilis. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/pluteus_admirabilis.html