tiny omphalina?

[diggleken]

Hi everyone,
this was nestling under the wings of russula ochroleuca yesterday, 4 or 5 of them in the moss around it.
Substrate is peaty heathery soil with some silver birch around, quite damp with lots of sphagnum too, which is where they were found.
Extremely tiny, half a cm cap width, funnel shape, decurrent broad gills - from Jordan surely the description seems right for Omphalina postii, but he describes that as rare, so that makes me hesitant!
Grateful for any help.
Cheers
Ken

[Chris Yeates]

hi Ken

is there a possibility this could be slightly over-exposed?

postii - now treated as a member of the small genus Loreleia should have an orange to orange brown stem, pruinose at the apex; this looks to have a stem with cystidia all the way up and I think the cap seems to have cystidia also . . . do you have any clearer shots of the cap - preferably in profile?

I suspect you may just have Rickenella fibula there

cheers

Chris

[diggleken]

Originally Posted by Chris Yeates

hi Ken

is there a possibility this could be slightly over-exposed?

postii - now treated as a member of the small genus Loreleia should have an orange to orange brown stem, pruinose at the apex; this looks to have a stem with cystidia all the way up and I think the cap seems to have cystidia also . . . do you have any clearer shots of the cap - preferably in profile?

I suspect you may just have Rickenella fibula there

cheers

Chris

Hi Chris,
thanks for helping - I know what you mean, I thought a rickenella too for a while, (and it may well be!) but having seen them recently, this was quite different I thought - this was what I had for them last week -

The new ''omphalina'' pic was exposed in sunlight to get more depth of field, its really tiny, about a pin size, so this was the only good pic I had. And so its a bit washed out, but not too much, the colours you see are pretty good and close to real life - so it is quite lighter orangey than the rickenella, with no darker ruddy cap colour as they had.
The cap seems to me to be scalloped as omphalina might be - but I dont have any experience with them, so dont know if that is always the case.
One final point - this was found as described, but in addition I didnt say (didnt realise might be important) the substrate is burnt (vandalised a couple of years ago) ground, with lots of sphagnum where the fungus was growing and when I googled some images etc found this thread contribution by fungiKen in 3/2008 :-

'..........Loreleia postii on the basis of the habitat. Here is what the Basidiomycota Checklist has to say about that species:

""Habitat: On burnt soil or soil with mixed ashes, often amongst Sphagnum spp., or large frondose liverworts such as Marchantia polymorpha or Lunularia sp.

Notes: Rarely collected or reported. Most records are from flowerpots in gardens or from burnt areas amongst Sphagnum spp. in boggy places." '

It has now dried and is so fragile and light , like a hair, but has blownaway I think, so no fruitbody to hand, but can go back.
Grateful for any further views - thanks a lot.
Cheers
Ken

[ManwithNoname]

The problem with finding something potentially uncommon is that you really should rule out the more common species first, and then provide strong evidence that it is the species you suspect, before putting a definite name to it.

Sometimes it's easy to go down the path of wishful thinking. For example, there may be sphagnum present in the surrounding habitat, but the moss tangled around the base of the mushroom isn't sphagnum and the microhabitat can be more relevant to what is growing there than the wider environment e.g. it might actually be a relatively dry patch in an overall boggy area. These are the sorts of things you need to keep in mind when noting relevant information relating to your finds.

I agree with Chris that your specimen might just as easily be washed out Rickenella fibula and we have no way of ruling that common species out. So without more information I'm afraid this is one you can't put a definite name to.

[diggleken]

Originally Posted by ManwithNoname

The problem with finding something potentially uncommon is that you really should rule out the more common species first, and then provide strong evidence that it is the species you suspect, before putting a definite name to it.

Sometimes it's easy to go down the path of wishful thinking. For example, there may be sphagnum present in the surrounding habitat, but the moss tangled around the base of the mushroom isn't sphagnum and the microhabitat can be more relevant to what is growing there than the wider environment e.g. it might actually be a relatively dry patch in an overall boggy area. These are the sorts of things you need to keep in mind when noting relevant information relating to your finds.

I agree with Chris that your specimen might just as easily be washed out Rickenella fibula and we have no way of ruling that common species out. So without more information I'm afraid this is one you can't put a definite name to.

I agree it could be both - and I dont do wishful thinking for rare or unusual species, I've been around birds too long for that - I am presenting more facts to try and further establish what it might be with expert input, but I understand exactly where you are coming from.
The moss it was growing in was sphagnum - the fact that I removed it to a sunnier site and laid it on different moss to photograph has confused you to think I was wrong, which is understandable!
No worries.
Cheers
Ken

[ManwithNoname]

Originally Posted by diggleken

I dont do wishful thinking for rare or unusual species, I've been around birds too long for that

... luckily with birds you don't (usually) have to squash bits of them on a microscope slide to get the right answer.

Originally Posted by diggleken

the fact that I removed it to a sunnier site and laid it on different moss to photograph has confused you

Agreed. Because the base of the mushroom appears in the photograph to be embedded in a tangle of uprooted moss which is not sphagnum I admit I was misled. I find that habitat shots from the actual habitat often pick up clues which may have been missed at the time of collection, and I usually study the surrounding habitat in any photo to add to the information available (although I recognise that it's not always possible to get the shot in situ for lack of light ... or lack of a wet suit etc.) In this case, the actual species of moss may not be significant. Loreleia postii grows in damp situations, often with sphagnum, but also in association with liverworts, such as Marchantia polymorpha or Lunularia, so a photograph of the actual habitat might have picked up whether these were present.

Originally Posted by diggleken

I am presenting more facts to try and further establish what it might be with expert input

Unfortunately, adding more facts about the macroscopic appearance or habitat often doesn't increase the prospect of a firm identification. The easy way to separate Rickenella fibula from Loreleia postii would be to look at the spores, which are much larger in L. postii.

However, if I was to go by the macroscopic information available, I'd probably plump for Rickenella fibula because, as Chris has suggested, the stem of R. fibula is pubescent along its length, whereas the stem of L. postii is hairless, but slightly pruinose at the top. From the photo, the stem of your specimen appears to be minutely hairy along its length. But without further microscopic details it would still only be a guess.