Hello.
Les périthèques semblent être immmergés... Pourrait-on avoir une coupe verticale de la chose ? Et un zoom sur l'ostiole ?
Dans tous les cas, ce ne sont pas les spores de H. mori.
Yannick

At higher magnifications the longitudinal 'slits' disappear.

The TS sections are the best I can make.

Any ideas?

Hi Carmel,

Definitively not an Hysteriaceae.

Perhaps you should look towards such species : http://www.ascofrance.fr/search_recolte/3665

Probably not a "true" Chaetoplea, but perhaps an idea for you.

Alain

 

PS : Does Rhamnus alpina occurs in Olea's area ?

Thanks Alain for you comments.

It does look similar to a Chaetoplea as indicated in the link. Unfortunately Rhamnus alpina does not occur in Malta. There are two other Rhamnus sp. (according to Stephen Mifsud's website) R. alaternus & R. oleioides. The area where I found this collection there were a number of thyme plants (Thymbra capitata) and I suspect that it may be a decorticated twig from this plant.
Within the Leptosphaeriaceae the only reported species (in Malta) belong to Leptosphaeria and a Neosetophoma but the spores are different here, so this is a new record for the islands whatever it is.

Other possibilities, I think, other than Chaetoplea are Curreya (if still valid) and Cucurbitaria but I have no literature on any of these genera.

I will open another thread to request the 1990 paper by Barr for dictyosporous genera in Pleosporalis (though it is for N. America) maybe it could be of some help.

Hi,

well, this is the unknown Thyridium I am also looking for. I have already a collection sent by you in 2016, and I have a comparable specimen from Cyprus, so I think it should be mediterranean distributed.

You should send it to Julia Checa.

Regards,
Björn

Hi Björn
          Thanks for your feedback.
          I had forgotten about the sample I sent to you. There are a number of common species between Cyprus and Malta, quite interesting.
  
          I will contact Julia Checa and keep you updated on any progress.

Interesting discussion... 

The habit and colour of the substrate is most probably Thymus capitatus , while I can safely exldue Rhamnus spp. In fact, I have seen something similar also on thyme in the island of Gozo, but which I have not collected. If I encounter something similar I will collect and update you.

Thanks Stephen for your comment.

Just to conclude this topic.

I have received an email from Julia Checa and she is of the opinion (from the photos) that the specimen looks like Dyrithium lividum (Pers.) M.E. Barr.

This species has been reported by Saccardo (as Thyridium lividum) in 1914 (no.47) and 1915 (no 95) and in fact in the latter entry one collection is from Thymus capitatus. It seems to be common as indicated in the last line of 95.

Thank to all for your input.

No, this is not Dyrithium lividum, this is another species, I definitely do not agree with Julia. Sorry.

I have recently examined a collection of Dyrithium lividum, this looks quite different. I am adding two photos of the spores of this species, and I am sorry that the recolt was in a very poor condition. You can compare with Enrique Rubio's collection right here on ascofrance:

http://www.ascofrance.com/search_forum/28080
http://www.ascofrance.com/search_forum/18537

Your species is something else, probably belonging to Thyridiaceae (similar to Mattirolia).

regards,
Björn

I have encountered the afore-mentioned population and this time I photographed and collected them. Will study them later. I think I have two different kinds of black ascomata, one looking similar to those reported by Carmel the other more clustered and elevated (or simply they are same species but younger). All found on the surface of dead or almost dead twigs  of Thymus capitatus, often at the lower half or third om bark-exfoliated stems.

If anyone wants to examine them, I can send some samples. I'll report the micro features soon, when time allows.

Hi, so as not to override Carmel's post I am reporting my observation of my Thyridiaceae species growing on Thyme on a seperate post. Link below:

http://www.ascofrance.fr/forum/47068/thyridiaceae-with-an-oval-stroma

I think they are the same species but better not assume anything at this stage.

By the way, what families are closely related to Thyridiaceae that might be considered?

Many Thanks