Myxo on Balsam Stem - for ID Help Please.

[Lancashire Lad]

Hi all,

I've had this for over a week now, but am struggling to get anywhere with it:



Found growing on a live, but horizontally lying stem of a Himalayan Balsam plant.

The sporocarps were the typical glossy white colour when found on site, but by the following day, they had changed to what can be seen in the photo. Typical size at that time was about 1mm across. The white specks on the sporocarps are limy deposits.


Now, a week later, they physically look much the same, although the Balsam stem section has dried, and the sporocarps have slightly shrunk as a result, being now only in the region of 0.75mm across.

To me, they look reminiscent of some of the Didymium/Diderma species.

Spore mass (under dissecting microscope) very dark brown.

Spores spherical, measured at ~10-11 microns.
Spore colour pale yellowy brown under transmitted light.
Under oil immersion, spore surface can be seen as extremely finely warted with scattered patches of slightly darker but still extremely fine warts.
(At x600 the spore surface looked completely smooth).

I looked very hard to find any remnants of capillitia/elaters - but on the three sporocarps looked at so far, can't find anything.

Can't find anything obvious that might narrow all the possibilities down.

Any suggestions towards ID very much appreciated.

Regards,
Mike.

[Marja]

Hi,

if there is no capillitium, look for the answer from Liceas.
There is for instance Licea minima, but maybe not this one.
Sorry, that I don't know brittish species...

Marja

[Lancashire Lad]

Thanks Marja.

I have looked at details for all of the British Licea species that I have information on in my books.

There are also several Licea species listed on the FRDBI which don't appear in my books, and I've looked at what information I can find on those too.

Many of the sessile Licea species have facetted or plate-like sporocarps, and none of those that don't seem to match with my find.

I will have a look at a couple more sporocarps under the microscope tomorrow, just to fully satisfy myself that there are no capillitia remnants to be found. (but after looking hard on the ones I've already scoped, I really don't think that I'll find any).

Regards,
Mike.

[stickman]

Hi Mike

I too think this could be a Licea species.

I have seen L.parasitica and L.variabilis look a bit like this, but I don't think the spore size fits for the latter and the habitat would be atypical.

Is there any chance of a shot of the spores? Licea spores can be quite distintive...and one of the peridium would be good too.

Licea parasitica. (Zukal) G.W.Martin

Cheers,
Nick

[Lancashire Lad]

Hi Nick,

Unfortunately, these are about the best that I can get with the Minicam:-
(Viewing at largest size is very slightly better).

1st. photo close up of peridia (at about x40 via dissecting microscope).
2nd. photo one sporocarp teased away from substrate to try to show rear surface and plane of attachment.
3rd. photo spores at x600
4th. photo spores at x1000





I examined another four or five in total, but still couldn't find anything at all that might have been remnants of capillitia/elaters.

Regards,
Mike.

[Kevin Lawson]

Hello Mike,

I am also going to go for Licea – because of the lack of capillitium.

On the basis of your spore measurements and the ornamentation shown in the photographs I would say L. variabilis.

The habit would not be right for Licaea variabilis and this species more usually forms long plasmodicarps – but I can’t see what else it could be.

Regards,
Kevin

[Lancashire Lad]

Hi Kevin,

Thanks for your suggestion.

A Licea does look likely due to the complete lack of capillitium.

But looking at the description of L.variabilis in Ing, etc., and also on sites which I would expect to have properly identified photos, overall, it does seem quite different to my find.

Mine definitely didn't go through a brown phase, before maturing as in the photo, and there is no mention in what I've read/seen so far, about L.variabilis having lime encrusted peridia.

As you say, the substrate would be wrong too, with L.variabilis (as far as I can establish) said to be found on decaying conifer wood.

I know that in the real world, organisms don't read the text books, and in the world of fungi in particular, species are often found where they "shouldn't be". So I dare say that could well apply to Myxo's too.

Thanks everyone for all the suggestions, but I think on this one, unless someone has a sudden inspiration, I'll resign it to the unidentified file - with a "possibly Licea sp." tag.

Regards,
Mike.

[diggleken]

Hi Mike,
if Kevin, Nick and Marja are going Licea, I'd put it at Licea spp.
Cheers
Ken

[stickman]

Hi all,

I've had a pretty extensive look through 'Die myxomyceten and your description doesn't seem to match any of the 50 or so species mentioned

Using the synoptic key using sporocarp size, spore colour & size it out leads to L.testudinacea, but we can't see any peridial plates

I also wonder about the 'lime deposits' - I recall a few authors commenting on the plasmodium's gelatinous nature and that debris can often be found stuck to the peridia....

Cheers,
Nick

[Lancashire Lad]

Hi Nick,

Definitely no peridial plates. - When Licea was suggested, and I saw that several species have such plates, I looked at every one of the sporocarps with the dissecting microscope, just to be certain.

I accept what you are saying re possibility of debris sticking to the peridia, but I'm as certain as I can be that the white deposits that you see on the photo (and on all of the sporocarps in my sample) are embedded into the peridia in the same fashion as you would see on some Physarum sp. etc.

Certainly a strange one! - I've spent about three hours today searching the web and can't find anything that seems to be near enough the same.

I'll certainly keep a look out in case I happen upon any more, that's for sure!

Ken - I'm slightly reluctant to tag it as definite Licea sp. because it just doesn't seem to fit well enough with any particular sp. (But then again - there doesn't seem to be any reasonable alternative species that it could be either. ).

Well - No-one ever said they would be easy.

Once again, thanks for all help/suggestions.

Regards,
Mike.