Observation 136079: Polyporales sensu lato

When: 2013-06-09

Collection location: Nescopeck State Park, Pennsylvania, USA [Click for map]

Who: Dave W (Dave W)

No specimen available

Resupinate with flaring cap-like appendages that are white on top.

Proposed Names

28% (1)
Recognized by sight: effused-reflexed
26% (6)
Recognized by sight

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Irpex lacteus
By: Irene Andersson (irenea)
2013-06-12 23:57:26 PDT (-0700)

is a better match than Gloeoporus or Cerrena with this shape and size of the spores. Also with the overall looks, it’s the best suggestion so far.

In Irpex lacteus you should be able to see plenty of incrusted cystidia. They may be there, but I’m not sure (polypores are difficult in the microscope)

By: Dave W (Dave W)
2013-06-12 19:56:45 PDT (-0700)

The spore size was the one factor that led me away from Gloeoporus. So I’m wondering about how reliable this character may be in this case. The spore quotient reported for G. dichrous fits this observation.

I tried to separate the pore layer from the context that attaches to the substrate, but the entire layer of material lifts from the substrate. I’m guessing that an old G. dichrous may lose the “pores separable from context” trait as the fungus ages/dries. Thickness of entire fungus (my collection) ranges between 1.5 and 3 mm.

I got a photo of hyphae, and will add to post… not that this will actually settle anything. Looks like there’s no real hope for consensus here. But this is all part of the humbling experience of mushroom ID.

Thanks again everyone, for the proposals and discussion.

Looking again
By: Christian (Christian Schwarz)
2013-06-12 12:49:21 PDT (-0700)

at the hymenium, I think they are much too pore-like for Irpex, but also a little too much for my suggestion of Cerrena. I’m leaning towards Gloeoporus at this point.

The color of the pore surface…
By: Dave W (Dave W)
2013-06-12 09:30:04 PDT (-0700)

is accurately reflected in the photo. Very thin context along surface of attachment to substrate (under the pores) is white.

Danny, did you view the second photo of the pore openings viewed through the eyepiece? This photo, with material held at an angle, shows the elongation of some of the tube-walls.

Kuo reports that the pores do not become tooth-like near the margin. I’ll post another photo tonight which shows non-tooth-like pores near the margin.

Could this be a dried-up Gleoporus dichrous? Except for the spores for this one being too long, G. dichrous seems to fit.

With such a range of pore orientation,
By: Danny Newman (myxomop)
2013-06-12 07:03:11 PDT (-0700)

I would expect this to have developed considerably more elongation into the familiar teeth-like projections of I. lacteus to be considered as such. I could see a very young or small I. lacteus being less toothy, but this is fully mature and reflexes almost the point of imbrication. There simply isn’t enough dissepiment here, IMO, to call this I. lacteus. Plus, if I’m not mistaken, even very old I. lacteus tend to remain whitish/cream-colored as opposed to the dingy brown seen here.

Even with the material in hand…
By: Dave W (Dave W)
2013-06-12 05:00:22 PDT (-0700)

I’m still wavering as to what to call this.

Actually, having re-read Phillips’ description of Gleoporus, except for the spore size, this seems to fit the profile of an old-dried up G. dichrous. Sausage-shaped spores form this specimen are 40-50% longer than as reported for G. dichrous. But the quotient ~ 3 matches G. dichrous spores.

Near the margin where the caplets flare out the pores are more regularly polygonal/circular.

Tonight I’ll try to prepare a better mount of the context and look for hyphae. More photos forthcoming.

If nothing else, I’m at least learning some stuff about these resupinate pored fungi!

Irpex vs Cerrena
By: Christian (Christian Schwarz)
2013-06-11 21:34:01 PDT (-0700)

The Irpex I’ve seen have really strongly toothed/slotlike “pores”; more three-dimensional so to speak, whereas Cerrena I saw back east had more pore-like angular holes in the hymenium (like these, in my opinion).

Yeah, the green-ness of Cerrena is dependent on age (it mostly grows after the spores quit being produced as far as I can tell, and the fruitbodies persist well after that). I think algae is less dramatic on Irpex but I’ll defer to other folks to weigh in on that.

Irpex lacteus
By: Jim Tunney (Jim Tunney)
2013-06-11 20:56:55 PDT (-0700)

sounds good

My first thought…
By: Dave W (Dave W)
2013-06-11 18:45:29 PDT (-0700)

had been Gleoporus dichrous. Profile in Phillips seemed to match this one. But the tube layer is reported as “rubbery.” My specimen has a hard (very thin) tube layer. This may be due to the specimen being old and dried out. But when I scoped a bit of material I found some spores, and they are too large for G. dichrous. So I think we can rule out G. dichrous.

Cerrena unicolor also looks like a good fit. But one thing that does not match Kuo’s description is that the pores on my specimen appear to be more polygonal than slot-like, especially near the margin. Although, there are a few areas within the pore surface that look like elongated openings. Except for near the margin, “tubes becoming tooth-like”, matches both C. unicolor and Irpex lacteus. Spores observed in my specimen show q>2, which makes them a better fit for I. lacteus than C. unicolor. Also, “subcylindric” (Kuo’s description of I. lacteus spore shape) seems a good fit for the spores seen in this obs. But the age of this specimen may be taken as a reason to suspect that the spores have shriveled a bit.

Not sure what to make of the micro photos. I looked at a bit of material that I shaved off the specimen. A few of the shots show projections that ?may? be cystidia. I’m not very familiar with these features on polypores. The one shot appears to show hyphae, but I don’t know how to interpret this info.

Thanks for your input, Jim, Christian, and Walt.

By: Martin Livezey (MLivezey)
2013-06-11 18:03:26 PDT (-0700)

So that is Cerrena unicolor! The field guides always show it as a green polypore but w/o a good gill shot. Yeah I see this all the time. Now I can post it.

Created: 2013-06-10 21:20:19 PDT (-0700)
Last modified: 2016-03-06 21:26:43 PST (-0800)
Viewed: 164 times, last viewed: 2017-10-31 03:34:25 PDT (-0700)
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