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18-06-2018 04:55

Andgelo Mombert

Bonsoir,Sur tige morte de Gentiana lutea, en compa

11-06-2018 20:34

Andgelo Mombert

Bonsoir,Sur tige morte de plante, probablement d'A

18-05-2018 18:38

Riet van Oosten Riet van Oosten

Hello,Found 17-05-2018, The Netherlands.On: Phragm

17-06-2018 00:36

Alan Rockefeller Alan Rockefeller

Looks like what is passing for Caloscypha fulgens

14-06-2018 22:33

BERNARD CLESSE BERNARD CLESSE

Bonsoir à toute et tous,Voici un Saccobolus trouv

14-06-2018 12:55

Savic Dragisa

Hi, I need help for this Helvella species. I found

15-06-2018 12:19

Pintos Angel Pintos Angel

anybody can help wiht this?Koskela P (1983) Arthri

15-06-2018 09:45

Yannick Mourgues Yannick Mourgues

Bonjour. Je suis à la recherche de : - Rivista

13-06-2018 12:01

Bernard Declercq Bernard Declercq

Hi to all, I would be very pleased to receive a p

06-06-2018 14:42

François Bartholomeeusen

Dear forum members, On Equisetum fluviatile I fou

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Dematiaceous synnematous fungus on bark.
Stephen Mifsud, 31-10-2016 04:19
Stephen MifsudHi, I am challanged with a fungus I found on decaying bark, about 0.5-1.0mm long. It has a yellowish-tobacco stipe, quite tough and sometimes developing a black sheath or just it becomes black at the base, supporting a reproductive structure which is irregularly round or ovate, covered in a greyish olive-green mass of spores. This is also quite tough and a cross section reveals a pale medulla and a dark green cortex.

Its when I examined the reproductive part under the microscope I got confused. in my limited knowledge I interpreted that the fungus is composed of a densely packed layer of tubes which are likely basidia but perhaps ascii, each forming forming ONE terminal spore. I don't know of any basidiomycete which is monosporous, while I wonder if ascomycota form spores this way since usually they are inside an ascus. The remaining alternative is some Myxo (size and habitat OK) but still I'm not sure there were no obvious signs of a plasmodium.


Well the what-so-called basidium is 16-19 x 5um, cylindrical with sinuated-irregular margins, while the spores are 7-8 x 3-3.5 in size, narowly lachrymoid with an acute-pointed end (attachment end) and with few small oil bodies, probably with a smooth surface.


See captions for further details

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Stephen Mifsud, 31-10-2016 04:25
Stephen Mifsud
Re : Dematiaceous synnematous fungus on bark.
More images
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Marja Pennanen, 31-10-2016 07:30
Re : Asco or Myxo ?
Hi Stephen,

you can forget the idea of this being a myxomycetes. Myxos do not have septas. Some imperfect fungus perhaps...

Marja
Alain GARDIENNET, 31-10-2016 07:50
Alain GARDIENNET
Re : Asco or Myxo ?

I agree, it looks like an hyphomycete.


Good luck to find a name !


Alain

Stephen Mifsud, 31-10-2016 09:05
Stephen Mifsud
Re : Asco or Myxo ?
Thank you both - always learning something new :-)

So is there a big possibility that this is not even an Asco?  If you look closely at the 5th pic of the second post I think that those stuctures are clamp junction, and so, this would exclude ascomycetes as somewhere I read that Asco cannot have clamp junctions.  Thanks alan , I need lots of luck - so let's check Hyphomycete !
Stephen Mifsud, 31-10-2016 22:30
Stephen Mifsud
Re : Asco or Myxo ?
Ok guys, finally I think I have a name oir this strange species!!!

Penicillium claviforme


Look here one before last photo:
 http://www.tub-collection.com/pic.html
Pintos Angel, 02-11-2016 16:11
Pintos Angel
Re : Asco or Myxo ?
 I think you can forget also that it is a Penicillium. In Penicillium conidia are borne in chains from phialides.

What I think I see is a Dematiaceous Hyphomycete with conidiogenous cells polyblastic, integrated maybe  sympodial, denticulate.

un saludo 
Angel 
Stephen Mifsud, 02-11-2016 19:44
Stephen Mifsud
Re : Asco or Myxo ?
Thanks Pintos angel.

In fact, apart the lack of spores in chains, I was also concerned with the shape of the spores which in penicllium are almost always sugglobuar or globular, but this fungus have narrowly-lachrymoid spores.   I take your suggestion and discard Penicillium.  Any other suggestions are welcomed
Stephen Mifsud, 07-11-2016 16:57
Stephen Mifsud
Re : Asco or Myxo ?
Hi,

I am still trying to identify this fungus, at least genus level. I have drawn a representative diagram of what I think I am seeing. See images.

I hope that the stipe structure can be regarded as a coremium


The best guess is somewhere within Stilbaceae (Stilbum, Briosia, Pycnostysanus, Stysanus, Coremium....)

In KOH the fruiting body turns black.
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Stephen Mifsud, 07-11-2016 18:42
Stephen Mifsud
Re : Asco or Myxo ?
What about Didymostilbe sp. ?  Is there a monograph available ?
I've cultured on PDA, MEA and Czapek - growth very slow or almost nil.

Pintos Angel, 07-11-2016 19:48
Pintos Angel
Re : Asco or Myxo ?
Aqi tienes una descripcion abreviada, Didymostilbe conidioforos hialinos, fialides hialinas, las fotos que pones son pigmentadas
Angel
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Stephen Mifsud, 08-11-2016 09:03
Stephen Mifsud
Re : Asco or Myxo ?
Thanks for you scan and you are probably right, not everything match up with that genus, although only by few characters. Does the book mention closely related genera?


Unfortunately, now I am running out of options. I think that I have checked all the 'important' genera of Stilbaceae, and I can't think of another Family for this synnematous ascomycete. (Tuberculariacea maybe?).  I still have some specimens to share, and if someone is interested to check just email me  your postal address on [marz @ nextgen .net .mt] (remove spaces) and I will send some material - as it can have a potential to be a new species to science from the M altese islands / Central Mediterranean. It is distantly related to Seifertia (=Briosia) azaleae  a pathogen of Rhododendron.


Regards