Is this a Russula Graveolens?

[Boatgypsy]

I think I have an identification, but just wondering if anyone can confirm it from this picture.

Many thanks.
Ian

[fairplay]

Hi Ian, and welcome to WAB.

If you know this is a Russula species, then you will know how extremely difficult they are to identify to species level - especially by photo alone with no other information.
Only microscopic examination would be able to confirm which species you have.

Neil.

[Boatgypsy]

Originally Posted by fairplay

Hi Ian, and welcome to WAB.

If you know this is a Russula species, then you will know how extremely difficult they are to identify to species level - especially by photo alone with no other information.
Only microscopic examination would be able to confirm which species you have.

Neil.

Hi Neil, I don't "know" that this is a Russula, I only know that it looks a bit like other pictures I have seen of Russula Graveolens, hence my question. I was not aware that they could only be identified by microscopic examination. As I don't have the means to do that I guess I will never know!

Thanks anyway.

[mollisia]

Hello,

it is definetely a Russula species and it is nearly same secure to say it is a Russula from the group of the Xerampelinae (or Viridantes as some prefer). If you would have put FeSO4 on the stipe surface, you would have seen a greenishgrey reaction. All other Russula species have a pinkish-orange-yellowish reaction.
The species of this section are not to determine at the moment, as we are waiting on a monographic treatment of that group, which will result in many new descriptions and interpretations.

best regards,
Andreas

[Ken Burgess]

The group of species formerly lumped together under a broad concept of Russula xerampelina share a characteristic smell, described as fishy or crabby, almost as though they were rotting, even when in good condition. So you can usually narrow it down to this group quite easily from the smell alone. You can then confirm it from the green reaction when the stem is rubbed with iron salts.

Getting down to species level is more problematic, bearing in mind that the taxonomy keeps on changing, as Andreas has indicated. According to current thinking Russula graveolens is one of the more common species in this group in the UK, found under broadleaves and often with a brownish cap. But more characters would be needed to firm up the identification.

Ken

[Boatgypsy]

Many thanks for your replies.

So at least it looks like I'm on the right track with a Russula!

Can anyone tell me if Iron Sulphate is the only diagnostic test. I ask because I have easy access to Iron Chloride, and I wonder if that iron salt would also be diagnostic. What is the chemical in the fungus that reacts with FeSO4 to give the colour change?

Cheers,

Ian

[mollisia]

Hello Ian,

to my knowledge it is the trimethylamin (= (CH3)3N ; C3H9N) that also causes the fishy smell in those mushrooms and is also in charge of the yellow-brownish discolouration where it was manipulated.

best regards,
Andreas