Xeromphalina kauffmanii

Description

Xeromphalina kauffmanii is a species of agaric fungus in the family Mycenaceae. The cap of the fruit body is convex, sometimes with a central depression at maturity. Its color is initially bright rusty orange, changing to bright orange to cinnamon in maturity. The narrow, light yellow to cream gills. It has yellowish fibrils surrounding its base, as well as white rhizomorphs attaching the base to the substrate.

The mushroom has thin, cream-colored flesh with an indistinct odor and a taste that is initially mild before becoming slightly bitter.

Xeromphalina kauffmanii fruits in dense groups or clusters on rotting hardwood logs and stumps.

The very similar Xeromphalina campanella appears on the wood of conifers and has slightly wider spores.

Xeromphalina kauffmanii and its relatives are not edible, but not poisonous either. Each mushroom is so small that it would be hard to collect enough to make a meal anyway. Plus they are so tough and rubbery that you'd have to spend half an hour chewing each bite.

Mushroom Identification

1. Ecology

   Saprobic on the deadwood of hardwoods; growing in dense clusters (sometimes by the hundreds!) on stumps and logs, or occasionally growing in small clusters or even alone; spring through fall; widely distributed east of the Rocky Mountains.

2. Cap

   0.5–2 cm across; convex to broadly convex or flat overall, developing a deep central depression; bald; becoming lined or pleated, especially toward the margin; brownish yellow to brownish orange or orangish brown; paler towards the margin; fading.

3. Gills

   Running down the stem; close or nearly distant; with many cross-veins; pale yellow; short-gills frequent.

4. Stem

   1–2.5 cm long; 1–2 mm thick; more or less equal, or tapered to the base; rusty yellow above, darker brown below; bald, or sometimes with orange basal mycelium; wiry.

5. Flesh

   Insubstantial; yellowish.

6. Odor and Taste

   Not distinctive.

7. Chemical Reactions

   KOH bright red on cap surface.

8. Spore Print

   White.

9. Microscopic Features

   Spores 3–6 x 2–3 µm; ellipsoid; smooth; weakly to moderately amyloid. Pleuro- and cheilocystidia fusiform to narrowly clavate; up to about 30 x 10 µm. Caulocystidia clavate to fusiform; thin-walled. Pileipellis a cutis; elements 3–15 µm wide, encrusted, orangish, clamped at septa.

Photo sources:

Photo 1 - Author: Katja Schulz from Washington, D. C., USA (CC BY-SA 2.0)

Photo 2 - Author: Hamilton (ham) (CC BY-SA 3.0)

Photo 3 - Author: AmatoxinApocalypse (AmatoxinApocalypse) (CC BY-SA 3.0)