That's a good question. I have spent lately some time with Arachnopeziza aurata, even studied one herbarium specimen of A. delicatula (det. R. Korf). During the recent years collecting in Scandinavia has resulted in several observations of A. aurata, but not with a single collection of A. delicatula. Thinking about the variation in septation/size in A. aurata I don't think it is possible to distinguish between these two species. ...meaning all these recent collections belong to one species genetically, but spores fit to both descriptions. The base of the hair is one thing, but so far I have failed to observe any morphological pattern.

I can't rule out the existense of A. delicatula completely, but no sign of it yet. I think Zotto has a folder called "delicatula"...what ever that means :-).

cheers,
Timo

Hi Ethan & Timo

I see the problem, but I think that when you restrict the spore analysis on mature spores (freshly ejected), you will have in A. aurata mainly 7-septate spores and in A. delicatula mainly 3-septate. The total absence of 7-septate spores in delicatula collections supports this.

Timo, did you ever find A. aurata on conifers? My folder delicatula is purely cpnifericolous, if I did not overlook something, and in my database on A. aurata is purely on angiosperm hosts.

Now, your, Ethan's, collection is obviously on an angiosperm, the wood surface looks so. I have no experience with American collections.

Ichecked available sequences and find that it is rather confusing. Above all, there does not seem to exist a sequence of a typical European A. aurata! ITS tree attached here.

A. delicatula is only present with one Japanese strain. Florian Prell's A. aurata is very distant, and I do not have a docu of it. But I have a folder that I call "aurata Ulex", it was previously "ulicis" in the Parachnopeziza folder.

Timo, do you have an ITS sequence and where does it cluster?

Zotto

all right. I didn't realise the connection between "delicatula" folder and conifers. Nope, I have absolutely no records of A. aurata (or anything with long, slender spores) on conifers. It's on Betula and Populus here. All the aurata material I have would cluster there among Japanese/American aurata's. In Zotto's tree the other two A. aurata below are most definately something else.

Timo

News about A. aurata: I made a mistake with Florian Prell's number, it is not 388 but FP155 (see attached trees).

I have checked in CBS by querying for his sequence and got 100% A. aurata from France, F. Mangenot (without location and eco-datam CBS 116.54), of which only LSU exists in the GenBank. So there's some sense in Florian's find and sequence!

In addition, I have overlooked two unpublished sequences of us. One is again this "ulicis" on Ulex wood, which falls to the American aurata and which I considered a Parachnopeziza when studied.

The other is A. aurata from Luxembourg, on Carpinus wood, which falls 100% to FP155.

I had not considered that a ITS few sequences are quite incomplete and cause extreme distances in the tree under Neighbor-joining.

Therefore, I have now calculated a tree with maximum likelihood and the result is attached. Also I calculated a tree which includes only 5.8S and ITS2, which contains only complete sequences and run under NJ.

This means that Japanese and American A. aurata do not seem to be true A. aurata.

Now Timo, it would really be interesting to include your sequences in the alignment. I would send the alignment to you if you want to check.
Zotto