Observation 198459: Annulohypoxylon thouarsianum (Lév.) Y.M. Ju, J.D. Rogers & H.M. Hsieh

Species Lists


Green KOH extracted pigments (courtesy of Werdnus)
Annular discs (courtesy of Werdnus)
Scale in µm (courtesy of Werdnus)

Proposed Names

30% (2)
Recognized by sight: Annular discs, interior tissue. Will require spore morphology to ID to species.
-41% (2)
Recognized by sight

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Eye3 = Observer’s choice
Eyes3 = Current consensus


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No problem
By: Troy (Troy)
2015-02-21 02:55:48 FNT (-0200)

and thanks for taking a look! I’d love to see the photos and add them to the observation so I’ll shoot you an email.

Specimen arrived!
By: Roo Vandegrift (Werdnus)
2015-02-20 18:47:54 FNT (-0200)

Great looking slide, by the way. And absolutely lovely material.

I made a second mount in Melzer’s, to try to have a look at the apical plugs, but the asci in this species seem to be effervescent — I didn’t see any either. Seems like Ju and Rogers had the same issues, actually.

Spores measure (17-) 18.9 (-20) x (4-) 4.5 (-5) µm (from measurements of 10 spores). Germ slit is hard to distinguish, but looks to be spore-length, on the flattened sight, straight to slightly sigmoidal.

That makes it pretty solidly Annulohypoxylon thouarsianum. I’ve got a couple of cell-phone-through-the-microscope snaps showing the scale bar and a close-up of the ostiolar discs, if you’d like to add them to the observation. Sent me an email, and I’ll reply with the photos attached: werdnus [at] gmail [dot] com.

Thanks again for letting me look at this lovely material!

By: Roo Vandegrift (Werdnus)
2015-02-13 02:15:56 FNT (-0200)

I look forward to it! I’ll let you know when it gets here.

By: Troy (Troy)
2015-02-12 23:46:31 FNT (-0200)

I’ll ship it tomorrow. I included a specimen in case anything happens to the slide. And since tracking was free here’s the tracking number: 9400109699938184558024; just so you know where it is.

By: Roo Vandegrift (Werdnus)
2015-02-12 15:01:24 FNT (-0200)

I usually wrap the slide tightly in saran wrap and then tape it to a piece of stiff cardboard, and then place an equal-sized piece of cardboard over it, making a slide sandwich, and then ship in a padded envelope (the kind with the little bubble wrap built in). Write “DO NOT BEND” on the outside, which is the cue for the USPS to hand-sort instead of machine sort the letter.

Sealing the slide would probably be a good idea.

What would
By: Troy (Troy)
2015-02-12 13:05:39 FNT (-0200)

What would be the best way to ship a slide so that it doesn’t get broken? And should I seal it with clear nail polish so the cover slide doesn’t move around?

By: Roo Vandegrift (Werdnus)
2015-02-12 02:19:13 FNT (-0200)

The sharpness of the ends of the spores is a really hard (and rather unreliable) feature with which to split species… I’d be much more comfortable making a determination based on size. If you want to send me part of the collection (or even just a slide) I’d be happy to measure the spores for you.

Roo Vandegrift
335 Pacific Hall
5289 University of Oregon
Eugene, OR 97403-5289

By: Troy (Troy)
2015-02-11 23:55:41 FNT (-0200)

I don’t have a microscope scale. I took another look at the candidates and I think Hypoxylon annulatum is a better choice.

I did manage to get a good mount but I ran into a few challenges with finding, identifying, and characterizing certain features and I don’t have Melzer’s so I couldn’t actually see the asci (it looked like a line of ascospores that were invisibly connected).

The spores looked smooth and I initially thought they had sharply rounded ends but I now think they were broadly rounded and I was looking at them from the side, making them look sharper than they were. They also had one concave side and one depressed side.

By: Roo Vandegrift (Werdnus)
2015-02-11 20:15:35 FNT (-0200)

Did you get a size for the ascospores?

to look at spores
By: Roo Vandegrift (Werdnus)
2015-02-11 01:17:38 FNT (-0200)

Awesome! Glad it’s looking figure-out-able; looks like a really excellent collection.

If you can, when making a slide it’s best to look at the asci, as well as the ascospores, preferably mounted in Melzer’s reagent. The tip of the ascus stains blue in the Melzer’s, and its shape and size can be informative, helping to distinguish between similar species.

I usually use the tip of one side of a pair of very fine forceps to remove the black goop from inside the perithecia. If the specimen has dried out, you can just rehydrate a single perithecia with a drop of water.

Ah, thank you
By: Troy (Troy)
2015-02-11 00:22:31 FNT (-0200)

I’ve narrowed it down to a few species using that key (I think Annulohypoxylon thouarsianum).

I’ll let some spores collect overnight and take a look at them under the microscope tomorrow.

“concentric zonation”
By: Roo Vandegrift (Werdnus)
2015-02-10 23:25:01 FNT (-0200)

The concentric zonation of Daldinia is an alternation of white/black or light/dark that’s pretty distinctively different from the “zones” in the big hemispherical examples of Annulohypoxylon. Your shots are lovely, and show the annular discs around the ostioles perfectly, so there is no doubt about the genus. The species, on the other hand, will require some microscopy, if you want to figure it out. Try this key: http://mycology.sinica.edu.tw/...

(The section Annulata of Hypoxylon has been moved to its own genus, the Annulohypoxylon, since this key was written. But it’s still the best available.)

Given the collecting location, you might also want to check out this paper, if you can get it:
Vasilyeva, L. N., Rogers, J. D., & Miller, A. N. (2007). Pyrenomycetes of the Great Smoky Mountains National Park. V. Annulohypoxylon and Hypoxylon (Xylariaceae). Fungal Diversity, 27, 231-245.

Created: 2015-02-10 23:13:35 FNT (-0200)
Last modified: 2016-01-04 06:10:39 FNT (-0200)
Viewed: 175 times, last viewed: 2016-10-24 14:06:27 FNT (-0200)
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