The
highlight of our Cain Foray 2001in Muskoka was by far the discovery of
the mushroom Macrocystidia
cucumis. We don’t know who did actually find it and where, other than
it was from the Huntsville area. It turned up at the sorting tables, not looking
like anything special. No one knew what it was. Maybe a Spathyrella, a Collybia,
or a Marasmius.
It was a cluster of smallish mushrooms with conical caps on long, slender stems,
all in a nice deep rusty-brown colour, with a lighter cap margin and stem apex.
The gills were pale at first, then becoming an unusual reddish ochre. One
difficulty was being unsuccessful in obtaining a colour spore print.
As
usual there was little time left for additional microscopic work after all the
day’s sorting, but late Saturday evening I found a little time to look at the
gill margin. What a surprise! A totally unusual forest of large, by mushroom
standards, cystidia covered the gill. Spindle-shaped (fusiform) cystidia of
50-100 : x 10-20 :
size, obscured the basidia. The cap surface looked like a carpet of cystidia
mixed with strange looking elements. Apparently these were the ends of hyphae
that make up the outer layer of the cap (the pellis). The stem was also covered
with cystidia. All by all, this makes the cap and stem appear velvety. The
spores were ellipsoid, smooth and 9 x 5-5.5 :.
With
all this new information, Dr. David Malloch of the University of Toronto’s
Department of Botany offered the suggestion that we could be dealing with a Macrocystidia
cucumis.
Except where was the cucumber smell which is variously described as that of
cucumber, herring, or putty, depending on the age of the specimens, the
temperature, or one’s nose. We did not detect any of those smells. However,
odourless variants have been reported in Europe.
Macrocystidia
cucumis was
originally called Naucoria
cucumis. The
genus has six species worldwide, but only one in Europe and North America.
Mycologists are not sure where to fit in this genus. It is now usually place in
the Tricholomataceae family. Flammulina
velutipes, the
Velvet Foot, might be its closest relative. The species is widespread in Europe
and becoming more so. It also occurs in western North America, mainly in the
northwest. For eastern Canada, this might be the first recorded find.