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21-07-2021 20:01

Chris Yeates Chris Yeates

Bonsoir tous I recently collected some dead stems

22-07-2021 21:15

Castillo Joseba Castillo Joseba

de hoy en tioerra dentro de un tocon vacio de haya

22-07-2021 08:40

Zuidland Peter

I found these today on Eucalyptus bark, apos to 2.

20-07-2021 15:08

Zuzana Sochorová (Egertová) Zuzana Sochorová (Egertová)

Hi, I have collected this ascomycete in a constant

20-07-2021 13:50

Garcia Susana

Hola, He recogido esta orbilia creciendo sobre ma

22-07-2021 19:03

Castillo Joseba Castillo Joseba

De esta mañana en un tronco de madera sin determi

21-07-2021 14:37

Juuso Äikäs

This solitary Scutellinia was growing on wet, mudd

21-07-2021 15:38

Michel Hairaud Michel Hairaud

Bonjour , Récolte du 13 07 2021 de ce Mollisia t

21-07-2021 13:09

Juuso Äikäs

Yesterday I found some rose-coloured Orbilias grow

21-07-2021 11:54

Edvin Johannesen Edvin Johannesen

Eggyolk-yellow disc, white hairs with distinct cry

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Diaporthe trinucleata - rare or overlooked?
Chris Yeates, 21-07-2021 20:01
Chris Yeates
Bonsoir tous

I recently collected some dead stems of Eupatorium cannabinum with the purpose of producing a composite image of Plenodomus agnitus (= Leptosphaeria agnita) which is common on that host in this area.

I noticed that among the numerous pseudothecia of that fungus there were much scarcer smaller fruitbodies mostly immersed in the host plant's cortex, and with pointed necks very different from the shallowly domed Plenodomus. From the apical ascal structure it was clear that this a member of the Diaporthales, and probably a member of the Diaporthaceae.

Having recently written up the Diaporthales for an ongoing Yorkshire Mycota I fully appreciate the nomenclatural and taxonomic issues with that order and might well have moved on. However there were a couple of interesting features: one was the complete lack of a septum, which pointed to what would at one time have suggested a member of Diaporthopsis (now sunk into Diaporthe), and the other was the high proportion (>90%) of spores containing three large guttules. Searching through Munk (1957) and Wehmeyer (1933) indicated that there was such a species and that it was a Eupatorium specialist - Diaporthe trinucleata Niessl. So I am quite happy to use that name for this collection, although I appreciate that sequencing might in future shed more light on this. Of interest is that on a few of the spores a hyaline conical appendage at each end of the spore could just be made out - easier to see than to photograph! Munk mentions no such feature and Wehmeyer specifically states he didn't see it, but Niessl in his protologue mentions "...utrinque obtusiusculis breve mucronatis hyalinis...".

I shall certainly keep an eye out for this taxon on further encounters with Eupatorium, and wondered whether anyone else had found it?

Cordialement, Chris
  • message #69568
Thomas Læssøe, 21-07-2021 20:58
Re : Diaporthe trinucleata - rare or overlooked?
I have made two Danish records on this species on that host (no notes available on the database, maybe with the material)


cheers

Thomas
Chris Yeates, 23-07-2021 14:18
Chris Yeates
Re : Diaporthe trinucleata - rare or overlooked?
Thanks for that Thomas. So the host relationship seems consistent - do you find Plenodomus agnitus to be rather common on Eupatorium in Denmark as well?

kind regards, Chris