Asco on oak gall

[stickman]

Hi all

This one has me troubled, I hope someone can help!

Found growing on (and firmly embedded in) a partially buried and decomposing acorn gall.





Apothecia 2-5mm. Microscopy as follows:

Spores smooth, cylindrical-ellipsoid average 6.1 x 2.9um
Asci cylindrical 80 x 100um, tips not reacting to Meltzer's
Paraphyses septate, filiform, sometimes branching.

Thanks for your time,

Nick.

[stickman]

OK bare with me - slight change of plan!

24 hours later I found this specimen on the same substrate & same location to those in the original post; so I suspect it to be a mature example of the same species. (although obviously I would like your opinions on this assumption!)





Microscopy for this one:

Spores smooth, allantoid, 0-3 septate, often budding at one or both ends. With several droplets. Average 17 x 4.9 um
Asci cylindrical, 120-150um (first post is supposed to read 80 - 100um). Tips blueing with meltzers.
Paraphyses same as OP.

Please excuse my poor photomicrography:






So am I correct in thinking this is a Rustroemia?

Cheers, Nick.

[Chris Yeates]

hi Nick

if you got mature spores out of the first one and they differed so much in their measurements from the second one, and differed in their Iodine response, I don't see how they can be the same species

the second one is Rutstroemia firma; I'll have a think about the first one

cheers

Chris

[stickman]

Nice one Chris, thanks.

I don't have a huge amount of experience with these ascos (but I'm learning quickly!)

I certainly got spores out of the first one, but not many and from a squash so figured it was possible I 'squished' them out of the asci prematurely.

Anyway I would be interested to hear if you can think of anything to fit.

Regards, Nick.