|Major Groups > Gilled Mushrooms > Dark-Spored > Gomphidius > Gomphidius subroseus|
by Michael Kuo
The slimy, pinkish cap, the gills that run down the stem, the "slime veil" sheathing the stem, the blackish spore print, and the yellowing stem base define Gomphidius subroseus, which is fairly widely distributed under conifers in North America--though it is much more common in the west under Douglas-fir.
Collectors have often noted that Gomphidius subroseus is frequently found with Suillus lakei in the vicinity, and it was long thought that this was a coincidence enabled by the fact that both mushrooms were mycorrhizal with Douglas-fir. However, recent research (see Binder & Hibbett, 2006) suggests that the Gomphidius can actually parasitize the Suillus, penetrating the mycorrhizae already established between the Suillus and the tree, and robbing both organisms of nutrients.
Cap: 3-5 cm wide; convex, becoming planoconvex; bald or finely appressed-fibrillose; very slimy; rosy red to pinkish, sometimes somewhat mottled with brownish to olive shades.
Gills: Running down the stem; close or almost distant; pale at first, becoming smoky gray; short-gills frequent.
Stem: 3-9 cm long; 5-10 mm wide; more or less equal, or tapering to base; with a fibrillose partial veil that is typically poorly developed and hard to distinguish underneath the "slime veil" (a thick layer of clear slime sheathing the young stem and covering the gills); at maturity slimy over the lower portion; sometimes adorned with a ring or ring zone that becomes blackened by spores; white above, bright yellow below; discoloring and bruising black.
Flesh: White in cap; yellow in stem.
Odor and Taste: Not distinctive.
Chemical Reactions: KOH negative on cap surface.
Spore Print: Purplish gray to black.
Microscopic Features: Spores 16-19 x 5-6 µ; smooth; narrowly ellipsoid or nearly fusiform; brownish in KOH. Hymenial cystidia cylindric to narrowly fusoid; hyaline; thin-walled; up to 130 x 15 µ. Caulocystidia similar to hymenial cystidia, but with encrusted apices. Pileipellis an ixocutis.
REFERENCES: Kauffman, 1925. (Miller, 1971; Smith, Smith & Weber, 1979; Thiers, 1985; Arora, 1986; States, 1990; Phillips, 1991/2005; Lincoff, 1992; Barron, 1999; Miller, 2003; McNeil, 2006; Miller & Miller, 2006; Trudell & Ammirati, 2009.) Herb. Kuo 08120304, 08130701.
Further Online Information:
Cite this page as:
Kuo, M. (2014, February). Gomphidius subroseus. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/gomphidius_subroseus.html