Observation 163773: Morchella exuberans Clowez, Hugh Sm. & Sandi Sm.

Growing in the “American Fire” zone of 2013.
Spores ~ 15.3-25.0 X 11.9-15.3 microns,ellipsoid and no oil droplets.
These match fairly closely to Kuo’s Morchella capitata which was superseded by Morchella exuberans.

Species Lists


Spore in Congo Red @ 1000X.
Spores in Congo Red @ 1000X.
Elements on sterile ridges in KOH @ 1000X.
Elements on sterile ridges in KOH @ 1000X
Elements on sterile ridges in KOH @ 1000X
Elements on sterile ridges in KOH @ 1000X.

Proposed Names

42% (4)
Eye3 Eyes3
Used references: Ascomycete Fungi of North America by M. Berg, Alan Bessette, Arleen Bessette.
Taxonomic revision of true morels in Canada and the United States; Michael Kuo et. al. Mycologia 104(5) 2012.
31% (4)
Recognized by sight: DNA analysis is need to differentiate NA burn morels (excepting M. tomentosa)
28% (1)
Used references: Pierre-Arthur Moreau
Based on microscopic features: Occasionally has capitate cystidia
Based on chemical features: 100% ITS match with the holotype of M. septimelata. Not a very good match for M. eximia.

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
I don’t think M. septimelata = M. eximia
By: Alan Rockefeller (Alan Rockefeller)
2017-05-19 15:44:43 CDT (-0400)

New information – check your email.

M. septimelata=M. eximia according to Richards et al 2014
By: Terri Clements/Donna Fulton (pinonbistro)
2017-05-19 09:49:15 CDT (-0400)

Re M. eximia: “=Morchella eximia f. multiformis Clowez, Bull Soc Mycol
France 126(3–4):327. 2012.
=Morchella anthracophila Clowez & Winkler in Clowez,
Bull Soc Mycol France 126(3–4):322. 2012.
=Morchella carbonaria Clowez & Chesnaux in Clowez,
Bull Soc Mycol France 126(3–4):326. 2012
=Morchella septimelata M. Kuo in Kuo et al., Mycologia
104(5):1171. 2012.
= Morchella eximia f. acuminata (J.Kickx f.) Clowez Bull
Soc Mycol France 126(3–4):329. 2012 (sensu Clowez,
And further: "All collections from Europe, Turkey and
North America (as Mel-7 or Morchella septimelata)
share an identical ITS sequence, except for the
holotypes of M. septimelata and M. carbonaria that
possess slightly divergent alleles (FIG. 2). The present
and previous multilocus phylogenetic analyses have
resolved all these collections as a single genealogically
exclusive lineage (O’Donnell et al. 2011; Du et al.
2012a, b). "

GenBank MF085525
By: Alan Rockefeller (Alan Rockefeller)
2017-05-19 07:49:25 CDT (-0400)
ITS sequence
By: Alan Rockefeller (Alan Rockefeller)
2017-05-11 10:42:16 CDT (-0400)

The closest match in GenBank is Morchella eximia, but this collection has a consistent 13 base pair difference with all the M. eximia sequences in GenBank.


Thanks Ron
By: Terri Clements/Donna Fulton (pinonbistro)
2017-04-14 00:28:22 CDT (-0400)

I’m no expert but it looks to me like any one of the 3 black PF morels is equally likely given macroscopic and microscopic characters. Definitely Morchella sect. Distantes though. We’ve sequenced some black morels from burn areas in Az and have documented both M. eximia and M. sextelata so far. We plan to do more this season.


I’ve added some micro photos
By: Ron Pastorino (Ronpast)
2017-04-13 23:28:54 CDT (-0400)

of elements of sterile ridges in KOH.
There were some that I would call capitate to subcapitate but not the most dominant form, which is more represented in the last photo.
Only checked one specimen.

Were there capitate cystidia on the ridges of this obs?
By: Terri Clements/Donna Fulton (pinonbistro)
2017-04-13 20:13:49 CDT (-0400)

About the chambered stem according to Kuo: “Although just about any morel can develop a thickened, chambered stem if it remains unpicked in favorable growing conditions,…” This specimen looks pretty old so I don’t think we know if it had it when young. Also from Kuo: " Unlike the apparently inseparable Morchella sextelata and Morchella septimelata (now M. eximia), however, Morchella capitata (now M. exuberans) appears to have some physical features separating it: its stem is often chambered and layered internally, and the elements on its sterile ridges, under the microscope, are “capitate,” which means they have roundish swollen ends. That’s my theory, anyway, based on examination of seven collections, six of which were fresh." The key is the last sentence—a theory based on a small sample.

By: Debbie Viess (amanitarita)
2017-04-13 19:53:19 CDT (-0400)

all you need to do is to look for the capitate cystidia on the ridges … or cut the base and look for that internally folded and chambered stipe.

this burn morel is both morpho and micro distinctive from eximia and septemelata.

Created: 2014-04-19 23:57:26 CDT (-0400)
Last modified: 2018-02-23 11:41:21 CST (-0500)
Viewed: 320 times, last viewed: 2018-06-15 20:11:49 CDT (-0400)
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