Hello Christiane,

According to van Brummelen (1995) in his World-Monograph Pseudombrophila dentata has ascospores less than 10 µm in diameter.
P. bulbifera on the other hand has ascospores more than 10 µm in diameter, it also has small sclerotia (especially in cultures) and a well developed subiculum.
This last feature is not always as well developed as it could be. 

You most likely found P. bulbifera. 
This probably is the first record in the Netherlands so safe some material.

Kind regards - Met vriendelijke groet,
Ron

Hello Christiane

Agree with Ron P.dentata, this one also has smaller apothecia that P.bulbifera. Congratulations on this find.

Regards.

Michel.

Chère Christiane,

OK également pour Pseudombrophila bulbifera (Durand) Brummelen. Oui,  les ascospores de cette espèce sont sphériques ou presque et mesurent, selon Brummelen, (9,5-)10-12,5(13) x (9,5-)10-12.3(12,5) ou 9,5-12,5(13) µm de diamètre et elles possèdent un contenu jaune dans le protoplasme, qu'on peut voir sur vos photos.

Très intéressante espèce !

Cordialement

René

Hi Christiane,

I surely agree with Ron, Michel and Rene! Also, would like to add even though I have never met any of these two sphaerosporic species that P. dentata should have (according not only to Brummelen 1995) more developed membranaceous margin often resulting in denticulate pattern (species name!) when apothecia are expanded. Your P. bulbifera has more scurfy structured margin, nicely documented by your excellent macrophotograph!

This collection surely deserves to be saved as an exsiccatum! What is also rather interesting in your obsevation is that you detected hair amiloidity! I can only encourage you to use lugol (by adding a drop on the cover slide edge) on every freshly prepared material you make in tap water medium!

Best wishes and good luck with your future work!
Neven

Thank you all for your determination help and encouragement

Kind regards - Met vriendelijke groet

Christiane

Hi all!
Today I have been studying Pseudombrophila bulbifera. Searching for info about it I stopped here. I tested with Lugol and I have not found hair amiloidity in my species. So I think that Christiane´s species can be an inmature Ascobolus brassicae, and what is seen stained in blue in her micro images  can be the asci. 
Cheers,
Raúl

Hi Raul! Hi Christiane!

Your distant-made-revision sounds very interesting! Good thinking! The spores fit nicely to the mature ones of A. brassicae too! And really, what is blue in Christiane's pic might be immature asci instead of hairs but what is trouble here is:

(1) ascospores still without ornamentation in A. brassicae should be smaller (at least concerning to those (four) collections that I've studied so far

(2) those ascospores (in lugol) looking completed to me as they are refractive and not vacuolate, also with rather completed wall thickness.

What might got happened here is that we had deviation I experienced with A. albidus for several times. In this species in some cases the ascospores may complete their development remaining hyaline without production of dark stripped ornamentation. I was so misguided by this that I thought I got an undescribed genus when I first saw this! Such spores were even capable to be normally ejected from living mature asci but did not have any germinated!

So, Christiane, can you try to get back to it: Do you remember or perhaps noted if ascospores were launched readily from asci or at least did you observed such refractive spores freely floating around the section without application of any squash (pressure) on the cover slip?

Cheers,
Neven

Hallo everybody,
Thank you all for looking once more at this topic and reconsidering the species. I can understand the doubt about the collection, because the similarities with A. brassicae are obvious. I too had and still have some doubts about it. The size of the spores resemble those of A. brassicae very well.
What did me think about not being A.brassicae was the missing ornamentation in the far developed state of the spores. Further I had never seen before such light brown colored hairs at the margin by A. brassica, a species I find here very often on rabbit dung. Another point was the difference in spore size in the asci of that collection. Some of them were (not always) much bigger in than others one ascus. I don´t have the world monograph of the genus Pseudombrophila of van Brummelen here, but I think that he wrote something about it, that often not all of the spores from P.bulbifera get fully matured. Indeed I found only few free ascispores in my preparations, but I did found some asci with open operculum.

Cheers
Christiane

Hi Christiane!

Your newly posted pics clearly demonstrate the lensiform operculum that is typical for Ascobolaceae! That do bring additional light on this problem! It is more and more likely to be the aberrant form of A. brassicae I have never seen so far or something new, at least to me (regarding the hairs!). This remains very interesting collection though!

Should you still have this material at your hand, it would be worth to try stain the unsqashed mature asci (with original periascal mucus intact) with lugol (living or dead). It is best to try make as thin apothecial vertical median section by hand as possible. In that way squash will not be necessary to see all cell types individually.

Cheers,
Neven