Observation 63688: Agrocybe Fayod

Original Herbarium Label: Agrocybe pediades (Fr.) Fayod
Growing in sand dunes.
In the UBC herbarium, there are two herbarium specimens referring to this Mushroom Observer observation: UBC F16601, identified by Paul Kroeger as Agrocybe arenaria, and the UBC F19929, identified by Oluna Ceska as Agrocybe pediades. Somebody added “var. semiorbucularis” to the UBC F19929. There is no indication who added this variety and why. Both collections are referred to as “Agrocybe arenaria?” in Kroeger et. al. 2012. Outer Spores


Proposed Names

-4% (4)
Recognized by sight: Does not look exactly like some of the A. pediades I have seen in grass. Very close though.
49% (6)
Recognized by sight
Used references: FAN6
Based on microscopic features: More micro details needed for species level identification.
Based on chemical features: Probably needs DNA work too as this may not correspond to any European taxon.

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

= Observer’s choice
= Current consensus


Add Comment
My email to Alan Rockefeller re changing the MO observation names
By: Oluna & Adolf Ceska (aceska@telus.net)
2016-02-21 19:20:48 CET (+0100)

On Sunday, February 21, 2016 00:10, Alan Rockefeller wrote us:

Who cares about the name? The important thing is the MO observation #. That is what ties everything together. Names change.

Here is my answer:
Hi Alan,
Thanks for your word of wisdom. I too relay on the MO Observation Number, but it is a tough luck when I have the herbarium specimen and am trying to find the corresponding MO observation. I stumbled across this problem when I was adding MO ### to the supporting herbarium specimens. MO database is unique by the fact that any yahoo can change the main database field (i.e., MO observation name) and the original user even does not have to learn about it. PLEASE, SHOW ME any other database, that would allow any passer-by to change its main field.
Who cares about the name? I agree, but then, why do you have to change it? PLEASE, STAY AWAY FROM CHANGING OUR OBSERVATION NAMES.
We greatly appreciate the interactive part of MO system, but if you have any other “name” to offer us, send it to us as a comment and let it on us to change the MO observation name AS WELL AS the name on our herbarium specimen. Physical accessioning of herbarium specimens is a slow process and before the herbarium specimen gets its accession number, the only tie between the MO observation and the supporting herbarium specimen are the names. …
I bet you had some professional mycologists that have suggested you to change your MO observation names. I bet they did it as a comment, but not by directly changing your observation name. Follow their example and don’t expose your citizen mycologist face to the MO viewers.

A. pediades group.
By: Byrain
2016-02-21 16:23:24 CET (+0100)

Might not be the best name when we still do not know the germ pore width or if there are pileocystidia or not. There is just enough detail to tell us its probably not any of the European taxa in that group.

Edit: To clarify, of the three specific features needed to get to the A. pediades group in the European keys, we have one of them and it doesn’t match. That is cheilocystidia length, germ pore width and absence of the pileocystidia would be the other two. With missing details its hard to tell, but the other direction in the keys does not look that good either. Its possible we have a non-European taxon represented here.

And no, feeding Adolf’s years long tantrum about naming conventions is not going to solve any of this, that horse has been beaten to death.

I am not trying to make you mad
By: Alan Rockefeller (Alan Rockefeller)
2016-02-21 09:20:45 CET (+0100)

I am trying to accurately describe your collection. Names change, but MO observation numbers do not. If you want to tie a collection to a MO observation, label the collection with the MO observation number.

I usually write out the full URL on the observation slip, just to make it obvious to anyone in the future how to get the photos.

Re: Alan Rockefeller change(s)
By: Oluna & Adolf Ceska (aceska@telus.net)
2016-02-20 20:07:30 CET (+0100)

MO is useless if you want to use MO for posting material that should go with the real voucher herbarium specimens. Never mind, enjoy making me mad!

Re: It’s a shame
By: Oluna & Adolf Ceska (aceska@telus.net)
2016-02-20 18:03:44 CET (+0100)

Apologies, my "Yes, it needs … "and your “Its a shame” messages met somewhere over the US/Canada border. Read the Notes to this observation. I think that it indicates the ID problems of this and Paul Kroeger’s collections.
Cf. also http://mushroomobserver.org/65616
Problem is that MO is an ideal database for collections without any supporting herbarium specimens (such MO observation are useless in our eyes). You run into the problems when you post MO observations that are supported by the herbarium specimen where the herbarium rules for the dealing with collections should have priority oven MO system of naming.
I am sorry, but I have to update our MO observations by adding the supporting herbarium specimen numbers, and I would like to has the same name on MO observations as there is on the supporting herbarium specimen.

Yes, it needs another closer look
By: Oluna & Adolf Ceska (aceska@telus.net)
2016-02-20 17:33:27 CET (+0100)

Sorry for bringing this up again. I have been adding Herbarium Specimen acession numbers (nothing else!) to our observations and the Time last modified default brings those unsolved issues back again. In the UBC herbarium, the supporting specimen of this MO is labelled Agrocybe pediades and filed in that slot. It is the specimen, not the MO observation that needs to be inspected and properly identified. If I file the herbarium specimen as Agrocybe, the collection gets lost in a garbage folder. However, if it is misplaced as A. pediades, arenaria, etc., specialists working on that group can fix it.
I.e., if you think that I have been digging up the old problems, I have not been doing that. I am just adding herbarium specimen numbers to make the proper ID easier and I am well aware that this collection needs another look. The collection proper is the key to solving this problem.

Its a shame
By: Byrain
2016-02-20 17:23:06 CET (+0100)

That you are not willing to address the discrepancies with the identification. All you are accomplishing is discrediting Oluna when its probably just your own failings that you are projecting.

I looked at this again.
By: Byrain
2016-02-20 16:10:12 CET (+0100)

And I missed that the cheilocystidia is too long for either A. pedadies or A. ochracea which should be up to 45 µm long. There are other taxa with longer cheilocystidia up to 60 µm.

However, there is not nearly enough info to identify this past genus. You will need germ pore width and presence/absence of pileocystidia at least.

No pleurocystidia
By: Oluna & Adolf Ceska (aceska@telus.net)
2016-02-19 19:19:20 CET (+0100)

Oluna did not find any pleurocystidia
(see http://mushroomobserver.org/image/show_image/135066 )
For various other ID suggestions see the Notes:

By: Byrain
2013-05-10 19:45:07 CEST (+0200)

Can you confirm that pleurocystidia was absent? Also for observation 65616, Agrocybe ochracea Nauta is a similar taxon with pleurocystidia. Assuming its absent, I agree with the name A. pediades.

Also, germ pore width seems important Agrocybe, your illustration shows this well, but did you happen to measure it too? :)

Re: stem texture
By: Oluna & Adolf Ceska (aceska@telus.net)
2011-02-20 22:03:56 CET (+0100)

We added a close-up of the stems to this observation, and yes, the stem was rough on our specimens.

Agrocybe pediades was the closest match to our material. As we understand it, Agrocybe pediades sensu lato is a variable complex that may include A. pediades s.str., A. semiorbicularis, A. arenaria, etc. Voucher specimen is deposited in the University of British Columbia, Vancouver BC under the name “Agrocybe arenaria” (UBC F16601). O+AC

stem texture
By: Alan Rockefeller (Alan Rockefeller)
2011-02-20 20:24:23 CET (+0100)

The texture of the stem in this collection is significantly different than what I would expect for A. pediades. When I find this taxon the stem is smooth.