Danny’s DNA Discoveries – Russula
by Danny Miller
Clade Russula “crown” - Russula zelleri group
The first 5 species have been going under the name R. cessans, a European Russula that may or may not be in this group (another possibility is the yellowing clade), but that does not actually occur here. Nobody had studied our R. 'cessans' closely before the study of Ben’s collections to notice that there are really multiple species, and even if they had, they are very difficult to tell apart from each other. Russula zelleri was described, you guessed it, by Burlingham in 1936 from Oregon, in the same publication where she described R. mordax, and similarly, not much attention was paid to it, but if it had been, we might have noticed long ago that what we have long called R. cessans over here was actually R. zelleri and other related species.
Here is an interesting story about a mushroom that does not occur in the PNW, R. lilacea, and how the very different R. zelleri group members were mistaken for it. In 1965, Darryl Grund’s UW PhD dissertation stated that the mild, dark yellow spored, purple European Russula lilacea was found very commonly in the PNW. He failed to notice that the description of R. lilacea was of a white spored mushroom, and he mistakenly stated that it was a yellow spored mushroom. He was actually finding members of the R. zelleri group. When Ben Woo made his Russula key in 1989, he followed Grund and stated that R. lilacea was very common in the PNW, but he did not copy Grund’s description of it, he went back to the original texts and wrote down the actual description of R. lilacea, not noticing the discrepency. So Ben’s key states that the mild tasting, white spored purple Russula lilacea is very common here. Then, many people happened to find a mild tasting R. phoenicea, a white spored Core clade member, and mistook that species for R. lilacea, not looking at the microscopy.
Russula zelleri
Russula zelleri itself is the third most common species in the group, occurring with spruce and pine. While usually purple, it has been noted to come in red or green colours too. There is a single ITS1 difference between recent collections and the 1936 Oregon type, and among the collections there may be 1 or 2 ITS2 differences.
R. zelleri © Ben Woo
Russula pseudotsugarum
The second most common species in the group, it can be found with spruce and pine as well, but also Doug fir and hemlock. It was recently named by Anna for its ability to associate with Doug fir (Pseudotsuga). It can also occasionally come in red or other colours. It is almost identical to the next species. One collection had a very, very grey stipe, but that may have just been unusual waterlogging.
R. pseudotsugarum © Ben Woo
Russula obscurozelleri
The most common species in the group, almost identical to R. pseudotsugarum and found near the same trees. It is named for its difficulty to tell apart from the other zelleri members. It can also fade to brownish yellow colours. One Washington collection tasted acrid, which confuses me.
R. obscurozelleri © Ben Woo
Rare relatives of R. zelleri
Russula sp. Woo 51
This rare species is very similar, purple or purple-red, found only twice with spruce and pine on the Oregon Coast. There’s no way yet to tell it apart from R. zelleri.
Russula “sp. 51a”, purple capped, was found once near Victoria BC and once in California under unspecified trees and cannot yet be told apart from any of the other 6 group members. I do not have a photo.
R. sp. Woo 51 © Ben Woo