Observation 202700: Fomes excavatus (Berk.) Cooke

When: 2015-04-12

Collection location: York Co., Maine, USA [Click for map]

Who: Erlon (Herbert Baker)

Project: Polypore Project

No specimen available


Hymenium hollowed out(excavatus).
Crust turns solution of KOH blood red due to the presence of fomentariol.

Proposed Names

-7% (2)
Recognized by sight

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
By: Erlon (Herbert Baker)
2015-04-14 20:54:06 CEST (+0200)

Here are some photo’s taken by the late Eugene Bossenmaier from Saskatchewan. You can see the same excavated hymenium. http://www.usask.ca/...

If you check other observations from northern central Canada you’ll see the same hollowed out pore surface. http://mushroomobserver.org/171105?q=2Xw50

It is more likely that Saskatchewan shares this species in common with the northern part of the eastern United States.

Correct Matt
By: Erlon (Herbert Baker)
2015-04-13 23:29:49 CEST (+0200)

As you can see, the groups span pretty large geographic areas.
The bottom group is from North America and China, the yellow highlighted taxon is from North Carolina, there are some collections from further west as well.

I suppose the question would be
By: Matthew Schink (MSchink)
2015-04-13 23:02:30 CEST (+0200)

whether all North American speciems group together or not, then go from there. The type for F.excavatus appears to be from Saskatchewan, a decent distance from the East coast. I would presume that F.excavatus was depreciated under the assumption that all F.fomentarius makes up a single cosmopolitan species. Which the DNA suggests is incorrect. So then we look at what separate names have been applied to North American specimens and compare as many characteristics as possible.

Here is one piece of evidence, “Originally described by Berkeley as Fomes fomentarius var. excavatus (Ann. Nat. Hist. 3 : 387. 1839). “The type specimens at Kew agree in all respects with P. fomentarius as it grows in the Adirondack Mountains…” (Murrill, The Polyporaceae of North America.— IV., 298, 1903)”

So according to Murrill the type specimen of F.excavatus matches F.“fomentarius” Collected in the Adirondacks, but does it match European specimens of F.fomentarius? And might there be several species of Fomes in North America that look quite similar to one another as there is with Ganoderma?

You are welcome
By: Erlon (Herbert Baker)
2015-04-13 22:48:27 CEST (+0200)

F. excavatus is the oldest name from north America with an available type collection. I’ve provided some more info on the description page that you can access by clicking on the name.

thanks for the reference,
By: Danny Newman (myxomop)
2015-04-13 22:41:57 CEST (+0200)

but I don’t see how that makes F. excavatus the best name for Betula-loving F. fomentarius-ish things found in North America and China. my point in mentioning that MycoBank lists the name as deprecated was to open up the floor to discussion on why you/someone else might believe it to be valid, rather than just deprecating it outright.

By: Erlon (Herbert Baker)
2015-04-13 22:20:20 CEST (+0200)

What is your point exactly? I’m well aware of the status of the name according to the various databases.

“Our strains clustered into two clades: the four strains isolated from the alpine range fell within a clade of F. fomentarius sequences with origin in the Northern European countries (Russia, Poland, Latvia, Slovak Republic, Germany, Austria, Slovenia), and F. sylvatica, Alnus spp., Acer negundo and P. abies as substrates. This Northern European clade is sister to a clade of F. fomentarius from the U.S.A and China from Betula spp. substrates.
Our Mediterranean strain (IB20130033) was placed within another, distinct clade of F. fomentarius sequences originating mostly from Southern European countries (Italy, France, Portugal, Slovenia) and other substrates (Platanus x acerifolia, Populus spp., Quercus spp. and Abies). The only exceptions are F. fomentarius sequences from the Slovak Republic. This Southern European clade is sister to a distinct clade of F. fomentarius from China.” (Dresch, Philipp, et al. “Fungal strain matters: colony growth and bioactivity of the European medicinal polypores Fomes fomentarius, Fomitopsis pinicola and Piptoporus betulinus.” AMB Express 5.1 (2015): 4-4.) http://www.ncbi.nlm.nih.gov/pubmed/25642401

By: Danny Newman (myxomop)
2015-04-13 21:58:02 CEST (+0200)

says it’s deprecated.

By: Erlon (Herbert Baker)
2015-04-13 19:53:34 CEST (+0200)

The hymenium is hollowed out. Excavatus means to be hollowed.

how does this differ
By: Danny Newman (myxomop)
2015-04-13 11:56:51 CEST (+0200)

Created: 2015-04-13 02:42:08 CEST (+0200)
Last modified: 2015-05-20 20:58:59 CEST (+0200)
Viewed: 327 times, last viewed: 2018-03-14 18:11:33 CET (+0100)
Show Log