Major Groups > Cup Fungi > Chlorociboria aeruginascens & aeruginosa


Chlorociboria aeruginascens & C. aeruginosa

[ Ascomycetes > Helotiales > Helotiaceae > Chlorociboria ... ]

by Michael Kuo

I had wanted to find the fruiting bodies of Chlorociboria for many years. Pictures of the tiny blue-green cups looked fascinating, and I knew that the many sticks and logs I had encountered with similarly stained wood were being decayed by the mycelium of this fungus, which is also "aeruginous" (Mycologese for "blue-green"). But while the stained wood is frequently encountered, the tiny mushrooms are seldom seen. I managed to see a black morel fruit from Chlorociboria-stained wood before I saw the fungus itself (see the bottom illustration).

This year I finally found the little blue-green cups, after years of searching. I took many photos--then promptly lost my collection bag on the way back to the car. So I am unable to tell you whether I found Chlorociboria aeruginascens or Chlorociboria aeruginosa, since microscopic examination is required in order to tell the difference (see below). I must have littered unintentionally, leaving a little waxed-paper sandwich bag covered with excited mycological notes somewhere in the north woods of Michigan for a hunter to find. I doubt Larry cares very much what "decorticated Quercus" means, but I hope he pockets the garbage and throws it away later.


Ecology: Saprobic on well decayed, barkless hardwood logs and sticks (especially those of oaks; "green oak" is valuable lumber); evident as green-stained wood year-round, but the fruiting bodies typically appearing in summer and fall; widely distributed in North America.

Fruiting Body: Cup-shaped at first, becoming flattened or disc-shaped; up to 1 cm across; with a tiny stem that may be central or somewhat off-center; smooth or slightly wrinkled; uniformly blue-green.

Microscopic Features: Spores 5-7 x 1-2 µ (C. aeruginascens), or 9-14 x 2-4 µ (C. aeruginosa); more or less spindle-shaped; smooth; with oil droplets at each end. Tomentum on upper surface delicate and composed of smooth, worm-like cells (C. aeruginascens), or more prominent and composed of roughened cells that look like spiny worms (C. aeruginosa).

REFERENCES: Chlorociboria aeruginascens: (Nylander, 1869) Kanouse ex Ramamurthi, Korf & Batra, 1957. (Sacardo, 1889; Ramamurthi, Korf & Batra, 1957; Smith, Smith & Weber, 1981; Arora, 1986; Phillips, 1991/2005; Lincoff, 1992; Barron, 1999; Roody, 2003; McNeil, 2006.) Chlorociboria aeruginosa: (Seaver, 1936) Kanouse ex Ramamurthi, Korf & Batra, 1957. (Saccardo, 1889; Ramamurthi, Korf & Batra, 1957; Smith, Smith & Weber, 1981; Miller & Miller, 2006.)

Aside from the microscopic differences noted above, some authors claim that the two species can be separated on the color of the flesh (orangish to yellowish for Chlorociboria aeruginosa; blue-green for Chlorociboria aeruginascens), and on whether the stem is usually central (Chlorociboria aeruginosa) or usually off-center (Chlorociboria aeruginascens). Bessette, Bessette & Fischer (1997) erroneously state that Chlorociboria aeruginosa does not stain wood.

Further Online Information:

Chlorociboria aeruginascens at Tom Volk's Fungi
Chlorociboria aeruginascens at Roger's Mushrooms


Chlorociboria species

Chlorociboria species

Chlorociboria species

Chlorociboria aeruginascens

Chlorociboria aeruginascens

Chlorociboria aeruginascens

Chlorociboria species
The blue-green stain of a Chlorociboria species, with a Black Morel growing in the same wood.

© MushroomExpert.Com

Cite this page as:

Kuo, M. (2004, November). Chlorociboria aeruginascens & C. aeruginosa. Retrieved from the MushroomExpert.Com Web site: