<Macroscopic characters>
cap size (in diameter) 11cm, 9cm, 5cm, 3.5cm
shape plane when young, depressed when mature
color brown with the center darker brown
surface smooth and moist, not hygrophanous
margin incurved when young, undulating when mature
gills decurrent, close, white to cream, unequal with short gills
stipe size (in length) 14cm, 13cm, 10cm, 8.5cm
(in thickness) 2cm, 1.5cm, 1cm, 0.7cm
central, solid, light brown, end enlarged and slightly
curved,
annulus (-), volva (-), white mycelium attached at the end
spore print white
odor mild, taste mild, latex (-), staining (-)
<Microscopic characters>
basidiospores 8.75~3.75 micrometers, spindle-shaped,
with small notche at both ends, not stained with
Melzer's agent(inamyloid, indextrinoid),
with four spores on each basidium
cystidia ca.30 micrometers long, elongated, partitioned into
small segments like an ear of corn (see drawing)
A basidium with elongated sterigmata was also found. (see
drawing) They may be the "germinated sterigmata" mentioned
in "North American Species of Clitoybe" by H. E. Bigelow.
<Comparison>
According to "North American Species of Clitocybe" by H.E.Bigelow, "C.avellaneialba is rarely confused with any other, except perhaps C.clavipes." However, in "Mushrooms Demystified" by D.Arora,it could be confused with C.leopardina. Therefore, I am going to make comparisons with these two species.
1. Clitocybe leopardina (no specimens found in the herbarium)
differences from C.avellaneialba
caps smaller (5-10cm), viscid brown that becomes paler in age,
gills pinkish buff with grayish tint that becomes yellower in age,
stipe shorter (3-6(-8) cm), thinner (1.5-2.5cm),
basidiospores more broadly ellipsoid (4.5-6∞~3-4ƒÊm)
None of these characters applied in my specimens, especially the color change in the cap and the shape of spores. Thus, there is very little possibility that my specimens are C.leopardina.
2. Clitocybe clavipes
differences from C.avellaneialba
caps smaller (2-10cm), grayish-olive brown,
gills white that turns yellowish buff in age,
stipe shorter (2-7cm), thinner (0.5cm-1.2cm),
odor fragrant (grape-like)
To summarize, C.clavipes is smaller than C.avellaneialba in general and the former has more yellowish gills. I made sure of these traits by comparing specimens at the herbarium. (C.clavipes : F12286, 13380, 15647, 15686, 15710. C.avellaneialba: F10261, 12011, 12151, 12213, 13607, 17827, 17828) I also had the impression that C.clavipes had a lighter brown cap than C.avellaneialba. In addition, comparing the specimens above, I noticed another possible differential character. The decurrent gills of C.avellaneialba gradually merge into the ridges on the stipe, which are formed during the drying process, whereas in C.clavipes, one can see a clear line that separates gills from the stipe. It is not merely a difference in color between the gills and the stipe, but a distinct termination of gills at the point of attachment on the stipe. The gradual transition of gills and stipe was found in the online images of the type specimen of C.avellaneialba at the herbarium of the New York Botanical Garden.
http://207.156.243.8/emu/vh/specimen.php?irn=731305
From the observations above, I conclude that my specimens are Clitocybe avellaneialba.
<The distribution of this species in BC (from the herbarium records)>
Three of the specimens were collected in the UBC Endowment Lands. There was one collected on Saturna Island (further detail unknown,) ca.48N, 123W. One from Squamish, 49.45'N, 123.10'W. One from Maple Ridge Malcom Knapp Research Forest,
49.16'N, 122.30'W. Therefore, C.avellaneialba seems to grow diffusely, at least in southern coastal British Columbia.
<References>
Howard E. Bigelow, North American Species of Clitocybe. Part 1. Gantner Verlag, (1982)
David Arora, Mushrooms Demystified: A Comprehensive Guide to the Fleshy Fungi, Ten Speed Press, (1986)
Matchmaker: Mushrooms of the Pacific Northwest, http://www.pfc.forestry.ca/biodiversity/matchmaker/index_e.html#menu
The New York Botanical Garden Steere Herbarium
http://207.156.243.8/emu/vh/specimen.php?irn=731305