Observation 66625: Morchella esculenta group
When: 2011-04-30
No herbarium specimen

Proposed Names

36% (11)
Recognized by sight: M. esculenta is a European species
-72% (8)
Recognized by sight
38% (5)
Recognized by sight
31% (2)
Recognized by sight
20% (4)
Used references: Kuo M., Dewsbury D.R., O’donnell K., Rehner S.A., Moore J.D., Moncalvo J., Canfield S.A., Carter M., Stephenson S.L., Methven A., & Volk T.J. “Taxonomic revision of true morels (Morchella) in Canada and the United States.” Mycologia 104.2 (2012): PDF.
31% (2)
Used references: Kuo M., Dewsbury D.R., O’donnell K., Rehner S.A., Moore J.D., Moncalvo J., Canfield S.A., Carter M., Stephenson S.L., Methven A., & Volk T.J. “Taxonomic revision of true morels (Morchella) in Canada and the United States.” Mycologia 104.2 (2012): PDF.
-2% (2)
Recognized by sight: IF this morel corresponds to what Kuo was calling esculentoides, californica is the validly published name.

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
apparent contradiction
By: Danny Newman (myxomop)
2012-04-20 02:55:59 CEST (+0200)

In the Great Lakes region, where the ranges of M. cryptica and M. esculentoides overlap, the two species cannot be separated reliably based on current data without molecular analysis.

and then

Based on current data the species cannot be reliably separated from M.
on the basis of morphological characters, although the hymenophore of M. cryptica is frequently somewhat paler and its ridges are usually more flattened. Microscopic features studied for the two species are virtually identical.

so it’s either indistinguishable, or it’s distinguishable by a paler hymenophore with flatter ridges…

as far as distribution and habitat:

Appearing in Midwestern hardwood forests, especially in apparent association
F. americana but also reported under L. tulipifera and Acer spp.; fairly common in the Great Lakes region from Ontario to central Illinois and western Pennsylvania; April, May and June. Specimens examined (see SUPPLEMENTARY TABLE I) were collected in Illinois, Michigan, Ontario and Pennsylvania.

Well, I think there’s no such thing as being 100%
By: Dave W (Dave W)
2012-04-20 01:57:55 CEST (+0200)

certain that a given mushroom is – and always will be – called whatever name I or anyone else assigns to it. Mushrooms, as well as our understanding of mushrooms, constantly evolve. Yet we sometimes agree to use a certain name under certain conditions.

So I’m wondering if M. cryptica is restricted to hardwood forsts of Ash and Tulip Poplar as is suggested by the most current research. Until someone demonstrates that M. cryptica occurs under apple trees and/or elm trees, I think I can rightfully call these types “esculentoides.” One possible macro distinction suggested by Kuo et al is whether or not the ridges are flattened. This is something I’ll try to keep in the back of my mind when I make collections of morels under elm/apple…. If we ever get any rain around here!

Something interesting about the apple tree “yellow morels” that I have been picking around here (eastern PA) for 20 years… Even when the apple trees intermingle with White Ash, after the productive apple tree has been dead for a few years, no more morels. The do not spread into the ash woods.

By: Danny Newman (myxomop)
2012-04-19 23:57:18 CEST (+0200)

in the eastern US, M. cryptica is described as being practically indistinguishable from M. esculentoides. no one can confidently “Call it That,” as in one or the other, as long as this problem remains.

edit: as corrected by Tom, the current known range is the Great Lakes area, not the whole of eastern NA, but that could very well change over time.

free access to Kuo et al. 2012
By: BlueCanoe
2012-04-14 00:42:02 CEST (+0200)

It looks like the Mycological Society of America (publisher of the journal Mycologia) has made the new Kuo et al. paper on morel taxonomy freely available.

Taxonomic revision of true morels (Morchella) in Canada and the United States

By: Patrick Harvey (pg_harvey)
2012-04-12 23:35:43 CEST (+0200)

I work at SLU. They do have a subscription to Mycologia, but only through 2008. Bummer.

Journal access
By: BlueCanoe
2012-04-12 18:42:21 CEST (+0200)

Head to your nearest college or university library for access to subscription-only articles. I’m pretty sure most libraries will let anyone walk in and use a computer to access electronic journals.

Michael Kuo’s article from last year
By: Patrick Harvey (pg_harvey)
2012-04-12 18:11:47 CEST (+0200)

Fungal Genetics and Biology 48 (2011) 252–265

Phylogeny and historical biogeography of true morels (Morchella) reveals
an early Cretaceous origin and high continental endemism and provincialism
in the Holarctic
Kerry O’Donnell, Alejandro P. Rooney, Gary L. Mills, Michael Kuo, Nancy S. Weber,
Stephen A. Rehner


By: Danny Newman (myxomop)
2012-04-12 18:04:19 CEST (+0200)

if I remember correctly, Tom Volk called this his paper at last year’s MSSF show.

timely indeed.

if only there were an MO kitty from which articles could be purchased to be made available on spare server space…

ah poo, payed subscription
By: Britney Ramsey (Riverdweller)
2012-04-12 16:59:26 CEST (+0200)

been wanting this one same as everyone! Guess I’ll have to wait.

By: Brian Looney (GibbiPicasso)
2012-04-12 05:03:28 CEST (+0200)
New Morchella names
By: BlueCanoe
2012-04-12 04:21:19 CEST (+0200)

This is timely. Kuo et. al’s new paper on morel taxonomy just went online today:

Taxonomic revision of true morels (Morchella) in Canada and the United States

Michael Kuo, Damon R. Dewsbury, Kerry O’Donnell, M. Carol Carter, Stephen A. Rehner, John David Moore, Jean-Marc Moncalvo, Stephen A. Canfield, Steven L. Stephenson, Andrew Methven, and Thomas J. Volk

Mycologia 2012 11-375; Preliminary version published online: April 11, 2012, doi:10.3852/11-375

http://www.mycologia.org/content/early/2012/04/10/11-375 (subscription required for full text)

By: Dave W (Dave W)
2012-04-11 22:13:33 CEST (+0200)

the “esculenta clade” idea is pretty appealing to me, as it seems more grounded in current scientific word usage than “group”. Although I personally like to call these “esculenta group” (and, as I had mentioned, the MO option is “I’d call It That”) I’ll drop the confidence level down to “could be” on my group proposal, and we can then see whether the community favors “clade” or “group”.

re: Patrick
By: Danny Newman (myxomop)
2012-04-11 20:03:49 CEST (+0200)

you’ve misinterpreted my meaning in the words “European name.” The names are derived from and applied in the continent of Europe. The connotation is geographic, not linguistic. My sentiment against their use has nothing to do with the languages spoken where the name is most appropriately applied.

The campaign against European epithets for NA Morchella is a matter of exercising caution, nothing more. In retrospect, I concede that [epithet] group is not so offensive for our continent’s Morchella members, at least until something better arrives, as the genetic similarity/phylogenetic proximity between and among Eurasian and North American species is close enough to warrant packaging them into groups/clades across continents. According to the paper BlueCanoe cited on another ob (http://ddr.nal.usda.gov/...), that seems to be the very direction NA Morchella taxonomy is heading (ie: Elata clade & Esculenta clade with basal M. rufrobrunnea).

This is a system I can swallow. It follows the lead of the most current and ongoing work in Morchella taxonomy, rather than blazing a potentially problematic trail of names and nicknames which may or may not have any basis in species relationships.

My $0.02.

By: walt sturgeon (Mycowalt)
2012-04-11 18:43:07 CEST (+0200)

Excellent comments. Morchella esculenta group is as good as we are going to get unless there are habitat/range differences or chemical reaction differences etc.
As for the little grey morels (some of us were calling them M.tulipifera for a while), I do think they are a different species than the M.esculenta group. They tend to fruit under tulip trees, ash and wild cherry. Those elongated verticle pits and small size are a distinct combination.
Also there are grey or “white” morels that remain that way unlike the tulip and esculenta types which turn yellowish. See the picture in Roody’s WV mushroom book, page 486. I have one site for these. Maybe they are an environmental variation as you suggest for tulip morels but I doubt it.

Why is the terminology
By: Dave W (Dave W)
2012-04-11 17:42:48 CEST (+0200)

“esculenta group” invalid?

It seems to me that, once this genetic code stuff gets even slightly sorted out, the existence of morphologically similar (if not virtually identical) “species” will require nomenclature that uses words such as “group”. Perhaps the fungal taxonomy is best viewed as an evolving process; not just the names (binomials) but the types of names. Maybe at some point we will discuss Morchella esculenta as it applies to a group of species, with additional terminology attached to address speciation. Maybe this will evolve into the new standard for ALL fungi, with the additional terminology subject to constant revision… as per Dan’s earlier description of rivulets separating from or recombining with other parts of the same river.

If this comes to pass, then – unless we adopt the habit of carrying around hand held DNA detectors – I seriously doubt that people will post obses on MO that include any taxonomic information that goes beyond the old – school binomials, (with the occasional “var.”).

So… we’ll be back to…. “Morchella esculenta”!

For now, it seems the real question is, "Do the NA yellow/gray morels formerly known as “esculenta” actually fruit from the same fungal organisms as the NA yellow/gray morels formerly known as “deliciosa?” My reason for wondering is that I often find the smaller “deliciosa” types fruiting in the same habitat as the larger “esculenta” types, and I suspect that the occurrence of these two types may be the result of the same organism reacting to different environmental conditions. Of course, this discussion would proceed a lot more smoothly if we could possibly agree to use some words.

And so, if the name assigned to the small yellow/gray morels with the sparsely and partially vertically aligned pits is “hamburgers”, then that seems to me to be a better option than “Morchella species”.

The linked obses below show yellow morels that fruited nearby White Ash at approximately the same time (extremely early, extremely dry conditions), about two yards apart, and when no other yellow/gray morels were observed in the area. It seems these may be fruiting from the same organism. I’d call the slender ones “deliciosa”, bit I’m not sure what I’d call the one with the thick stalk base.


Lastly (well, at least for now), the MO option is not called “What It IS”. The MO option is called “I’d Call It That”.

Good comments …
By: Patrick Harvey (pg_harvey)
2012-04-11 16:56:45 CEST (+0200)

Also, until each of us have (a) free access to a DNA laboratory, and (b) a way to post such data on this site, we will NOT be able to establish PRECISELY which
particular species we have, even after new American names have been proposed and approved.

But morphology does indicate which group of species corresponds to a particular observation. We can surely discriminate between which of three broad groups of Morchella is pictured.

Everyone here is free to start their own ExactMushroomDNAObserver site.

By: Brian Looney (GibbiPicasso)
2012-04-11 03:59:08 CEST (+0200)

Kuo has done some great work in establishing criterion for verifying the validity of the genus and identifying genetic diversity among North American collections, but this work has not been published in a peer reviewed publication and is, therefore, not established science. Morchella esculenta and Morchella deliciosa are established species that have been applied to eastern North American specimens for centuries, and we have no other recognized names to work with. Unless there is a reason to think, based on morphology, that what you find is different than these described species, then I think it is more informative to use the names than to refrain because it has been suggested that there is genetic differences.

By: Patrick Harvey (pg_harvey)
2012-04-11 01:13:27 CEST (+0200)

By your reasoning, you cannot call a spade a spade, as the word is derived from European languages … likewise with 80 percent of English.

It’s invalid
By: Danny Newman (myxomop)
2012-04-11 01:03:05 CEST (+0200)

to use an invalid name. If you are born in Russia from Russian parents and live and die in Russia, you’re not called an American. M. deliciosa is European. We in NA may have something similar, but it is not M. deliciosa, so calling it as such is akin to the aforementioned example. Language is a consensual delusion between and among animals shared via the respective body parts responsible for communication. I can call this thing I’m typing on a hamburger, but most know it as a keyboard. Just calling spades spades…

By: Patrick Harvey (pg_harvey)
2012-04-11 00:29:51 CEST (+0200)

Morchella esculenta & Morchella deliciosa are the only names we have presently to refer to yellow morels in the eastern U.S. Is it invalid to use a European name BEFORE American names have been created? I would not think that prohibition is part of The Code.

By: Danny Newman (myxomop)
2012-04-10 21:52:49 CEST (+0200)

is a European name

Genetic variation in individuals
By: BlueCanoe
2011-05-19 18:33:23 CEST (+0200)

Mycologists who use DNA are not suggesting that any genetic variation between individuals requires a new name. There are examples of DNA sequencing leading to “lumping” of what were formerly considered separate species as well (matsutake, for example).

Species concept limits
By: Patrick Harvey (pg_harvey)
2011-05-19 18:20:46 CEST (+0200)

Also, given the fact of meiosis (recombination) in spore production, at a certain level of detail EVERY individual organism is unique! This is especially true of fungi, most with many more mating types than the two sexes.

After a certain point, genetic distinctions are meaningless and unusable. I would rather classify a morel as M. esculenta, than obsess over the fact my identification of M. esculentoides var. northamericanus mating type X-2-13-44-797-B-12 MIGHT be incorrect.

I agree Dave
By: walt sturgeon (Mycowalt)
2011-05-19 17:16:54 CEST (+0200)

Good insight.

As I understand some of the
By: Dave W (Dave W)
2011-05-19 17:06:59 CEST (+0200)

relatively recent DNA based analysis of North American “Yellow Morels”, there are at least 4 data distinguishable “species”, and these are all virtually impossible to tell apart using any macroscopic criterion. So if each of these “species” eventually gets its own name, then such distinctions are essentially unusable… until the day when hand held DNA analyzers are available/affordable.

I think that the concept of species comes along with this question. Does a species entail organisms which exist only at one given point in time, or are organisms which had previously existed put into the same species as ones which currently exist? In light of evolution, I think that the concept may be well defined only when applied to organisms which exist together at some point in time. Given any sufficient list of conditions (criteria) that partitions the organisms which currently comprise the Kingdom of Fungi, there is the actual idealized “species” as it exists in Nature. The scientific understanding of the particular species is merely a shadow of this reality… the best we can do based upon available information relevant to the criteria.

On one level, it is the list of special criteria which is subject to revision. On another level, we hope to always have words available for the purpose of placing objects into categories, even if the words are subject to change from time to time. When the objects come from the Kingdom of Fungi, then the two levels often do not mesh very well… at least not presently. Then no appropriate words are available.

Or… we compromise and use names like “Morchella esculenta group.” As stated above, the scientific understanding of a “species” is an inherent compromise anyway.

With or without
By: Irene Andersson (irenea)
2011-05-18 19:43:31 CEST (+0200)

DNA “evidence” – I think Dan described the problem very well. We just can’t assume that we are, or ever will be, able to give every possible collection a name.

We will always potentially be “wrong”
By: Patrick Harvey (pg_harvey)
2011-05-18 18:05:21 CEST (+0200)

In the event that we finally have new names assigned for North American species, there will ALWAYS be the possibility that we have assigned the “wrong” name to our observations here on M.O. As before, without access to our own personal DNA laboratories, it is impossible to distinguish between many of the currently assigned European taxa. It will be proof beyond any REASONABLE doubt — and I for one will be good with that level of identification.

If it’s a yella, it ain’t JUST Morchella.

By: Irene Andersson (irenea)
2011-05-01 18:58:28 CEST (+0200)


If you look at the example with the gulls – no 1 and 7 do not interbreed, but where do you draw the line between them?

Re: Cladistics
By: Patrick Harvey (pg_harvey)
2011-05-01 18:40:06 CEST (+0200)

Very good comments, Shroomydan. I would prefer that before we split EVERYTHING between Europe and America that crossbreeding studies at least be done as a part of renaming proposals, in order to verify that separated species can no longer be considered distinct in that sense.

cladistics and all that
By: Dan Molter (shroomydan)
2011-05-01 17:42:40 CEST (+0200)


I also see the day coming when a new name will be given to every mushroom from North America that currently goes by a European name.

Molecular analysis will show divergent lines of evolution between European and American specimens, and this divergence will be used to justify splitting each species level taxon into two or more species. The underlining assumption is that species are evolutionary lineages, and that evolution proceeds in a continually bifurcating pattern. Each time evolutionary lines diverge a speciation event has taken place – but these assumptions are wrong. Lineages can diverge and yet remain parts of the same unit of evolution.

Imagine a population of animals that splits into two groups that become geographically isolated from each other. Geographic isolation yields reproductive isolation. At the very moment when the population separates, one unit of evolution splits into two. If the two populations remain isolated for two or three generations, then we would have little reason for considering them to be different species, but if the isolation lasts for many thousands of generations, then differences in molecular and macro morphology will accumulate to the point where animals from one line become readily distinguishable from animals in the other line.

Now imagine that the geographic barrier is removed and the two populations begin interbreeding again. At first there will be two main types and many hybrid crosses, but after many generations morphological characters will become homogeneous across the entire reintegrated population.

So how do we describe such a situation in terms of taxonomy based on the tree model of evolution? There are a couple ways to analyze it.

- The original species (SP1) went extinct at the moment the split occurred, and two new species (SP2 & SP3) evolved. When those two new species reintegrated they also went extinct, and a forth species (SP4) evolved.

- No speciation event happened at all.

- The original species (SP1) survived the split instantiated in one of the populations, but the other population becomes a new species (SP2) at the moment of the split. Upon reintegration either both SP1 and SP2 go extinct as SP3 emerges, or one of the branches survives and the other gos extinct. Whether SP1 survives or SP2 survives would depend largely on the number of animals in each population. If SP1 has a thousand members at the time of reintegration while SP2 has a million members, then it would be more reasonable to say that SP2 survived while SP1 went extinct.

- Other combinations are possible using the same kind of analysis.

This hypothetical evolutionary situation is better modeled as two channels flowing past a river island than it as a bifurcating branch on Darwin’s tree.

It’s easy to conceive of species as units of evolution when the history of evolutionary change is imagined as a constantly branching tree, but evolution is a bit messier than that.

“The very idea of a unit of evolution is much vaguer than might first have been supposed. The concept of ‘reproductive isolation’ suggests a picture of evolutionary change flowing down sharply defined channels, branching at well-defined nodes—and naturally identifies units of evolution as lengths of channel terminating at nodes. A more realistic picture would be a river estuary at low tide. We find large streams of water and many side streams, some petering out , others rejoining the main channel or crossing into a different channel, and a few maintaining their integrity to the ocean; there are islands around which streams flow and rejoin ; eddies and vortices; and so on. Some parts of the general flow are naturally and coherently distinguishable, and it is easy enough to recognize parts of the pattern that are definitely not parts of the same ‘unit of flow’. But in between, there are many cases where any such distinction into discrete units would be largely arbitrary” (Dupré 2001, In defense of classification, 207).

The upshot is that unit of evolution is too vague a concept to serve as the unit of classification.

this is ridiculous
By: Britney Ramsey (Riverdweller)
2011-05-01 17:17:03 CEST (+0200)

Yellow morel, grey morel, grey turning yellow morel? where’s the discipline in that?
If everyone took such liberties with names, this site would be a disaster.
The false naming should stop and be removed from the system.

I second Patrick on this.
By: Noah Siegel (Noah)
2011-05-01 16:53:55 CEST (+0200)

WHEN the name gets published start using it, until then keep calling it what we have been calling it for the last 200+ years. Or call it Morchella esculenta group or complex. Enough of bumping everything down to genus.

My thought is
By: Patrick Harvey (pg_harvey)
2011-05-01 16:29:51 CEST (+0200)

… to use the names we have UNTIL American species names are validated.
Although we KNOW that our species have distinct DNA, the names we use for them are still current. I believe it will eventually be ludicrous, when EVERY American species that differs only through slight genetic variation & not appreciably through morphology will have a new name.

Also interesting that a non-latinized name is valid here :)

Created: 2011-04-30 23:37:22 CEST (+0200)
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