Observation 104626: Russula mutabilis Murrill

When: 2012-08-10

Collection location: Bedford, New York, USA [Click for map]

Who: Linas Kudzma (baravykas)

Specimen available

Abundant Under Oak/Maple. Strong pleasant smell of almond. Taste hot. Firm brittle flesh with chambered stipe. Spore print white/cream and 22 spore print spores were measured. Spores globose to subglobose, amyloid in Melzer’s and (5.8-8.4) x (5.6-7.4) microns with an average Q of 1.14. Prominent raised spines.

Numerous cystidia with a “nipple” at end. I don’t have a reference that describes this for R. laurocerasi (now R. grata?). See photomicrographs.

Proposed Names

55% (1)
Recognized by sight
Used references
Based on microscopic features
62% (3)
Recognized by sight

Please login to propose your own names and vote on existing names.

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Will do Brian
By: Linas Kudzma (baravykas)
2014-05-07 15:57:06 PDT (-0700)

I actually used quite a few Russula to practice/develop my molecular technique and DNA extraction methods. This was one of them.

Hi Linas
By: Brian Looney (GibbiPicasso)
2014-05-07 15:24:55 PDT (-0700)

I have the sequence of the isotype of R. mutabilis, so if you send me your sequence I can confidently confirm whether it is or is not this species!

Brian, I have a nice clean ITS sequence and
By: Linas Kudzma (baravykas)
2014-05-07 09:42:55 PDT (-0700)

it is somewhat similar with the below two. I can send you my data if you wish.

98% Similar to:
Russula cf. subfoetens MICH73730
GenBank: KF245516

Russula laurocerasi
GenBank: AY061735

Thanks Britney!
By: Linas Kudzma (baravykas)
2012-08-10 12:33:06 PDT (-0700)
Lack of high crests
By: Linas Kudzma (baravykas)
2012-08-10 12:32:02 PDT (-0700)

or (wings as Philips calls them) bothered me also. However, the spore print is pale cream “B” color as defined by the Kibby & Fatto key. I’m looking at this publication right now and am missing Ray Fatto, who I knew very well. R. fragrantissima is supposed to have a yellow (C-D) spore print. I’m unaware if an American species closer to what I have here is formally described.

Thanks for your thoughts Irene.

R. grata
By: Irene Andersson (irenea)
2012-08-10 11:38:26 PDT (-0700)

in my books has spores with very high crests, rather than spines.
Gorgeous photos of those!
This looks closer to Russula fragrantissima. But according to http://www.rogersmushrooms.com/... ,
the american collections are different. Probably not the same as any european species, so I think you should look for american names here.

Welcome to MO
By: Britney Ramsey (Riverdweller)
2012-08-10 11:12:12 PDT (-0700)

Very nice microscopy.

OK Christian
By: Linas Kudzma (baravykas)
2012-08-10 10:12:05 PDT (-0700)

The other two prismatic spored finds are uploaded as 104628 and 104629. I’m scratching my head without better references.

By: Linas Kudzma (baravykas)
2012-08-10 10:03:33 PDT (-0700)

Yes Debbie, perhaps a bit too much empty magnification by enlarging this way. This is indeed a attractive and feature rich Russula. Too bad it is so peppery. The smell is wonderful.

beautiful sporograph!
By: Debbie Viess (amanitarita)
2012-08-10 09:44:13 PDT (-0700)

it is actually sharper if you don’t enlarge it, though.

how nice to find such a feature rich russula.

By: Christian (Christian Schwarz)
2012-08-10 09:23:48 PDT (-0700)

I’m not an expert, but it is the group I am most enthusiastic about studying.
Mostly I’ve focused on the western Leptonia types, seen a good number of Eastern Inocephalus, and a few Claudopus,Pouzarella, and a few Para/Eccilia

Thanks Christian
By: Linas Kudzma (baravykas)
2012-08-10 09:19:28 PDT (-0700)

I hope my knowlege of mycology can can catch up to my microscopy. I collected a number of prismatic spored specimens (104594 and 104507) that have me very unsure. Two more even more amazing ones will be uploaded today. Who’s an Entoloma (or whatever it’s been split up as) expert here?

Best microscopy
By: Christian (Christian Schwarz)
2012-08-10 08:38:17 PDT (-0700)

on this site in a long time. Nice observation!

Created: 2012-08-10 06:50:04 PDT (-0700)
Last modified: 2014-05-07 09:23:49 PDT (-0700)
Viewed: 162 times, last viewed: 2018-04-19 07:29:26 PDT (-0700)
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