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06-12-2024 16:10

B Shelbourne B Shelbourne

• Macro and habitat appear mollisioid.• Mollis

19-11-2024 00:36

Pérez del Amo Carlos Manuel Pérez del Amo Carlos Manuel

Hace unos días encontramos numerosos ejemplares d

02-12-2024 19:02

Margot en Geert Vullings

On a fallen branch, probably Acer, we found these

05-12-2024 16:38

Karl Soler Kinnerbäck

A Melastiza from Padjelanta, alpine Sweden, on cal

06-12-2024 10:28

Jiri Malicek

Hello, would anybody help me with ID of this unusu

05-12-2024 20:43

Juuso Äikäs

I found these black pyrenos a few days ago growing

05-12-2024 20:48

Stoykov Dimitar Stoykov Dimitar

Hallo colleagues,I need to consult a xylarialean c

30-11-2024 18:43

Yanick BOULANGER

BonjourVoici une récolte du 31/10/2024 sur boisJe

05-12-2024 18:11

Yanick BOULANGER

Bonsoir Quelqu'un a t-il une idée de ce que c'es

04-12-2024 18:31

David Chapados David Chapados

Would this be Jackrogersella or Hypoxylon?https://

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Chlorociboria aeruginascens
B Shelbourne, 01-10-2024 17:02
B Shelbourne• Habitat and macro suggest Chlorociboria.
• P Bjork suggests C. aeruginascens and C. aeruginosa can usually be distinguished by phenology and macro (in https://www.svampar.se/smf/smt/SMT_2016_2.pdf).
• Earlier fruiting, darker colouring and disc, and concolorous core of the stipe, seem to suggest C. aeruginascens, although the stipe is not eccentric.
• C .aeruginascens confirmed by spores.

Habitat: Old and well decayed deciduous wood, decorticated, mainly in the cracks and crevices, some localised blackening, with extensive turquoise (blue-green) staining (not necessarily indicating areas of fruiting), some bryophytes, on the floor, shady area and usually damp, no undergrowth, under mature trees, mixed deciduous woodland, Low Weald, England, mid-September, after rain.


Apothecia: Several groups, solitary to caespitose in small groups, diameter < ~3 mm, initially globose-urceolate, then cupulate and eventually discoid, short and thick stipe, often with a common base, when collected receptacle and stipe with smooth appearance, dull, greyish-turquoise, mottled with blackish patches, after one week in damp box more vibrant due to covering of short whitish hairs (all stages of maturity), margin like receptacle, initially in-rolled, progressively opening and eventually flattened, disc always appears darker, flat colour, more smooth and gelatinous appearance, becoming shallower and paler in maturity, surface apparently becoming more irregular.


Associates: Some small blackish globose lumps on the wood with hyphae protruding, often close to the apothecia.


Asci: Cylindrical-clavate, croziers, rings bb, apex rounded to conical-truncate when turgid, usually more acute when flacid, more hemispherical when immature, usually biseriate, with spores becoming trapped at the apex when flaccid, slight thickening when flaccid but more noticeable when immature.


Spores: Narrow cylindrical, +/- homopolar with ends rounded, inequilateral and rarely slightly curved in profile view, ~2-4 small to medium LBs and some smaller ones, often in groups towards the poles.


Free living spores in water: (6.8) 7.1 - 8.6 (9.5) × 1.8 - 2.1 (2.2) µm, Q = (3.2) 3.6 - 4.5 (5.1), n = 30, Me = 7.7 × 2.0 µm, Qe = 3.9.


Paraphyses: Cylindrical, apex rounded, not noticeably inflated at the apex, multi-septate (3-4 counted), often branching at the base.


Exudate: Deep turquoise, in hymenium and ectal excipulum.


Medullary: Textura intricata, with little to no exudate/pigmentation.


Ectal excipulum: Difficult to view with heavy exudate, very dark in patches, hyphae appear irregular and dense, shortish hyphae protruding from the surface, sinuous to irregular and hyaline.


Some elongated crystal-like structures found around the hymenium of more outer section, crunching when the cover slip was squashed, may be visible as a strange patch on the disc of most mature apo, happened in vitro, uncertain of explanation.

  • message #80299
  • message #80299
Hans-Otto Baral, 01-10-2024 20:37
Hans-Otto Baral
Re : Chlorociboria aeruginascens
Björk also mentions spore size which does not overlap in length (but he did not supply personal measurements).

My collection database goves for aeruginascens mainly VIII-X, rarely II-IV.

aeruginosa fuited on III-V, rarely XI.

The exudate I do not remember. Does it disappear in KOH?
B Shelbourne, 02-10-2024 13:29
B Shelbourne
Re : Chlorociboria aeruginascens
Thank you for the observation data. I was too vague and meant earlier in the autumn-winter season. The different size of the spores is constitent with your folders and descriptions I read, although the measurements in Bjork (from Dixon, 1975) seem to be on the smaller side for C. aeruginascens. I guess this could be related to vitality.

Good question about the exudate, that was my interpretation of the gelatinised appearance. I should test with KOH but unfortunately I didn't do it at the time.


I left a water mount for ~24 hours, and the colour faded to a brownish-yellow in the exposed parts (hymenium and ectal but not so much medullary), it is less opaque in the ectal but still appears gelatinised. Copious bacteria and some protists also developed in the mount.

Adding 3% KOH (only % I have) to this several times (to ensure %) did not have any visible effect on the pigments or gelatinised appearance, even after waiting several minutes and then agitating the cover slip and waiting again.


I have attached some photos. I think you can just about make out the textura epidermoidea in the second set.

Hans-Otto Baral, 02-10-2024 16:06
Hans-Otto Baral
Re : Chlorociboria aeruginascens
This is interesting that the green pigment fades in water! In the herbarium I guess the green pigment is stable but I amn ot sure.

If you add KOH to the green pigment it also disappears this way (I have a photo for the anamorph Dothiororina tulasnei by Martin Bemmann: Dothiororina_tulasnei_KOH_01).


B Shelbourne, 02-10-2024 22:47
B Shelbourne
Re : Chlorociboria aeruginascens
The colour persists in dried apothecial material at least, and has apparently persisted in wood for several hundred years.

The pigment, xylindein, seems to be relatively well studied due to its historic and commercial value in staining wood, and there is no known synthesis. The Tudor et al. (2014) paper, linking the anamorphs, says that Rommier (1868) first extracted the pigment, named it, and found it was water soluble.


It is reported to be produced in the hyphae and gradually diffuses through the substrate. A yellow pigment (or xylindein quinol) is also reported as occasional.

Hans-Otto Baral, 03-10-2024 06:32
Hans-Otto Baral
Re : Chlorociboria aeruginascens
Would be interesting to know how this pigment is chemically transformed to yellowish under KOH influence.
Martin Bemmann, 03-10-2024 15:07
Martin Bemmann
Re : Chlorociboria aeruginascens
The chemical structure of Xylindein is well known:


But I am no chemist. Reactions turning the pigment to yellow are reported:

DOI:10.5943/cream/6/3/10 (Weber et al. 2016)

Regards

Martin
  • message #80308
Hans-Otto Baral, 03-10-2024 16:37
Hans-Otto Baral
Re : Chlorociboria aeruginascens
Interesting polycyclic structure. Only I see no mention of any alcali as causing the break-down of the green pigment.