Danny’s DNA Discoveries – Russula
by Danny Miller
Clade Russula “crown” - Greying Russulas
Some Russulas with brightly coloured caps will turn grey after you scratch the stem (as the white Compactae group can). They might also turn reddish before turning grey. The two most common species are not that closely related, it’s just a coincidence that they behave the same in that regard.
Russula vinosa (occidentalis)
Another large Russula with olive colours in the center and purple colours on the edges (or perhaps either one of those colours). The spores are a only faint creamy yellow, not as dark as many in the crown clade. Scratch it and wait a few minutes to a few hours) and it will turn reddish and then grey. Russula vinosa was described from Europe and then our west coast species was later considered a variety of that mushroom, eventually getting a promotion and getting its own name, Russula occidentalis. Anna’s study showed that there is very litle genetic difference between our species and the original R. vinosa (perhaps 2 differences or so on average) so if that and the macroscopic differences are not considered enough to justify a separate species, ours would just be considered R. vinosa. It is found with various conifers.
R. vinosa (occidentalis) © Ben Woo
Russula sp. Woo 65
This fairly closely related species is rare and only found twice, once in Idaho and once near Glacier Peak, WA (near Doug fir and hemlock). The cap colours were yellow and dirty brown, and the yellow Idaho specimen was noted to faintly turn orange and then grey, like R. vinosa. If that is a reliable trait, it may be able to be identified if found again. Otherwise, it is going to be very difficult to recognize. (Russula sierrensis and R. aff velenovskyi, on the "Other Russulas" page, (along with Russula mordax on the "hot species" page), are also related but do not appear to demonstrate any colour staining).
R. sp. Woo 65 © Ben Woo
Russula sp. Woo 57 (aff vinososordida)
This large Russula is not in the same clade as R. vinosa, and represents a few species in a separate but similarly grey-staining group. It is also found with various conifers, but differs by usually having orange colours and a dark yellow spore print. When bruising is noted, sometimes a red stain is noticed before a grey stain, and sometimes only the grey staining is noticed. There are two European Russulas that match this description, R. decolorans (a Fries species from 1838) and R. vinososordida (from 2000, recently discovered to be a lookalike). Before 2000, it was assumed, of course, that our specimens were R. decolorans (the only known species at the time). After 2000, nobody thought to check to see which species ours was. These studies have shown that all 9 PNW specimens matching this description are 1% different than the type of R. vinososorda, not R. decolorans. This is probably a little too reliably different genetically to be considered to be R. vinososordida - a similar 1% difference separates the very different looking R. mendocinensis from both species. Also, our species is a conifer associate whereas R. vinososordida is a hardwood associate.
Russula mendocinensis, as I stated, is a very closely related mixed conifer-hardwood forest species (I’m not sure which trees it actually grows with) in California that can look and act surprisingly different. The type was purple, stained orange (but greying was not noticed), and was supposedly quite acrid tasting. However, a mushroom very much like R. vinososordida sequenced to be R. mendocinensis instead, so it may not always be so different. This will have to be looked into. R. claroflava (=R. flava), a bright yellow mushroom that stains reddish then grey, not yet known from the PNW, has been reported from here before but could represent sightings that were actually “aff vinososordida” or perhaps Russula sp. Woo 65. Russula flava var pacifica was described from Oregon, but it is clearly not a variety of R. flava, but very likely actually a “core clade” member, as stated on those pages. Save any yellow specimens you find that stain this way.
R. sp. Woo 57 (aff vinososordida) © Ben Woo
Russula sp. Woo 56 (aff californiensis)
Russula californiensis is second species closely related to R. vinososordida, a California pine species that is rosy red with a greying stem and mild taste. Our species is different and probably needs a different name (at least 6 substitutions and 2 indels different in ITS2, or >1.5%). It has only been found once with conifers (not pine) near Snoqualmie Pass WA, and was pinkish/rosy red with some greyish yellow tones. Although the greying in age or when damaged wasn’t specifically noted, it probably does. It was mild with creamy spores.
R. sp. Woo 56 (aff californiensis) © Ben Woo