Observation 67102: Agaricus crocodilinus Murrill
When: 2011-05-08
Herbarium specimen reported

Notes: growing in grass along treeless roadside, near coastal shrubs.

Species Lists

Images

145222
145223
145224
145225
145397
note giant spores!
145398
short gills, loooooong context.
145399
margin slightly inrolled even at maturity.

Proposed Names

95% (4)
Eye3 Eyes3
Recognized by sight: large firm white cap with stiff peaks like an Amanita magniverrucata, but with free, chocolate brown gills and a short stipe.
Based on microscopic features: giant spores (some up to 15 microns in length!)
Based on chemical features: smelled mushroomy (like portobella), with a very slight hint of almond.
KOH: negative on cap and context.

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Eye3 = Observer’s choice
Eyes3 = Current consensus

Comments

Add Comment
MushroomNut
By: Jacob Kalichman (Pulk)
2016-09-23 19:09:07 EDT (-0400)

Observation pages are for an individual observation of a mushroom – one finding of a species in one place by (usually) one person. Click “Create Observation” in the navigation bar to post your own photos.

MushroomNut
By: MushroomNut
2016-09-23 19:05:55 EDT (-0400)

Sorry, I didn’t know how to add a photo of the Agaricus crocodilinus I have. :(

Agaricus crocodilinus
By: MushroomNut
2016-09-23 19:04:59 EDT (-0400)

I just found this today in central Idaho, just north of Ketchum under a pine tree. At least I believe that’s what it is. I am doing a spore print on a smaller specimen. Could you please ID from the photo. I would like to try eating this, if it’s possible to get a correct ID from my photos.

Thanks!

Amazing specimen!!
By: Charles Seltenright Sr (Shroomin Yooper)
2011-06-13 05:13:08 EDT (-0400)
It is growing
By: Alan Rockefeller (Alan Rockefeller)
2011-06-12 22:50:28 EDT (-0400)

I gave my friend some gills from this collection and he was able to get the spores to germinate on peroxide agar.

Big is right!
By: Martin Livezey (MLivezey)
2011-05-11 15:25:45 EDT (-0400)

So I see there are both big and smaller spores here…, Is this a smash mount or spores collected from a drop? Is this croc. atypical? The top looks mature, but the short gills – are they immature? I would think an Agaricus like this one would be making deep spore prints every three hours…, Christian – maybe you should try these under your ’scope! Thanks Deb, this is almost as good as being there!

AWESOME
By: Christian (Christian Schwarz)
2011-05-10 22:50:53 EDT (-0400)
.
By: Debbie Viess (amanitarita)
2011-05-10 22:38:54 EDT (-0400)

A few comments from Rick Kerrigan (with permission):

“I don’t think the species [A. crocodilinus] has been confirmed from any further south than from your locality. Regarding spore size, here are my measurements on 280 spores from 13 specimens:

SPORES dark brown, ellipsoid, (8.6-) 9.2-11.2 (-12.8) × (5.8-) 6.2-7.7 (-8.6) um (longer on bisporic basidia) (N=280, C=13).

“Stresses including slow dessication can result in abnormal (including long) spores in many species.”

RK

micro shots added.
By: Debbie Viess (amanitarita)
2011-05-10 13:28:16 EDT (-0400)

still no sporedrop, tho. gill smash mount showed many enormous immature spores, some up to 15 micrometers! in water at 1000×.

note absurdly narrow gill width in comparison to context.

note inrolled cap margin, even at age.

KOH negative.

well Martin…
By: Debbie Viess (amanitarita)
2011-05-10 11:11:17 EDT (-0400)

since my report of the average sized spores (“only” up to 11 microns) was underwhelming to some, I am in process of getting a spore drop to see if I can’t find some of those super-gigantic spores. my first slide was a mere smash mount, and no doubt had lots of immature spores.

another curious aspect to this Agaricus is that the gills were extremely short…only a third of the length of the cap context! I’ll post that photo today, too.

still rockin’ the croc…;)

I love the excitement here, but…,
By: Martin Livezey (MLivezey)
2011-05-10 10:07:41 EDT (-0400)

Where is the microscopy? The microscopically challenged would love to see these big spores…, How ’bout it Deb? Great find either way!

no yellowing that I noticed…
By: Debbie Viess (amanitarita)
2011-05-09 14:10:17 EDT (-0400)

I’ll check again when I section it for the dryer.

any yellow bruising?
By: Britney Ramsey (Riverdweller)
2011-05-09 13:36:02 EDT (-0400)

Agaricus crocodilinus ‘var. mutabilis’ Isaacs nom. prov.

Agaricus crocodilinus Murrill var. crocodilinus Mycologia 4: 300. 1912

Which is this?

I wish I lived closer….
By: Tim Sage (T. Sage)
2011-05-09 13:27:42 EDT (-0400)

So I could go and touch it!

Time to reassess, Tim!

Super Wild!
By: damon brunette (damonbrunette)
2011-05-09 13:23:42 EDT (-0400)

Never heard about it or seen such a thing. Rod T. always says about spores varying a lot….. Must say though, that when physically touching mushrooms presents a thrill, one might need to reassess.

What a cool Agaricus!
By: caphillkid
2011-05-09 13:17:48 EDT (-0400)
.
By: Debbie Viess (amanitarita)
2011-05-09 12:48:33 EDT (-0400)

“up to 14 microns” is the outer range for giant spores; 8-11 is the norm. this is without a doubt crocodilinus, but I’m sure that Bruns can run the DNA if he so desires.
Come to the May BAMS meeting Erin, and I’ll let you touch it! A little piece of myco-history…;)

?
By: Erin Page Blanchard (CureCat)
2011-05-09 12:35:46 EDT (-0400)

Is “up to 11 µm” really a match for “somewhere around 14 µm”?

spores are a match.
By: Debbie Viess (amanitarita)
2011-05-09 12:01:35 EDT (-0400)

up to 11 microns in length.

Check the spores
By: Christian (Christian Schwarz)
2011-05-08 23:33:54 EDT (-0400)

They should be huge (for Agaricus) somewhere around 14 µm long.

PS – Totally badass! Nice find.

Created: 2011-05-08 23:20:12 EDT (-0400)
Last modified: 2016-09-23 21:22:20 EDT (-0400)
Viewed: 1536 times, last viewed: 2016-12-04 17:11:44 EST (-0500)
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