Fungi dispersal

[Dogghound]

Its quite clear how common fungi spread through the local area and radiate around the surrounding suitable habitat through spores in the wind, insects etc. But on a national scale a certain species that ive taken a particular interest in Guepinia helvelloides, which has a very patchy British distribution, with only around 5 sites in the UK carnt spread like this. The sites are so far away from each other, are these isolated relic populations that simply appear when a spore travels miles and strikes a suitable habitat which seems unlikely and extremely hit and miss with the distance between sites. Have they been reduced due to global warming? habitat loss etc? What is the possibility of this kind of species spreading to new sites? It seems that a slight change in habitat, management, landuse etc could totally wipe out a site making rare fungi very vulnerable. Are they spread by humans moving wood around which could explain the distance between sites.


Sorry afew questions. Cheers

Guepinia helvelloides
Guepinia helvelloides - Wildlife Photography

[mollisia]

Hallo,

many questions, and a very intersting theme.
I fear, that these questions, at least for the greater part, cannot be answered. We know too less about the circumstances where and why fungi species grow, to answer such questions. There are exceptions, yes, where the ecology is quite well known.

For your example of Guepiniopsis helvelloides (or better Tremiscus helvelloides probably): This is a species which is confined to calcareous soils or at last it is growing only when there are enough bases available in the ground. That may well be also in areas with acid soil, where this species then grows along those roads where calcareous stones where used for builing this road. Secondly it is said to be a mountainous species. So if these two parameters are true, the possible distribution in Great Britain is already quite limited.
Another fact is, that you often cannot judge from distribution maps, whether the species is that rare as the map shows, or if not enough data are in the map. Tremiscus helvelloides is on one hand a remarkable, very easy to determine species. But I cannot judge how representative the data are that are the base for this map. Are there guys in every part of the country who send data, or are there only here and there some an in greater parts no one looks for fungi? This makes it very difficult to interpret a give map!

As a mountaineous species, it may be, that Tremiscus helvelloides is declining by the climatical changes. However it is a species of calcareous soil, which contradicts this theses. We know from several examples of mediterannean species, that they are in their center of distribution (mediterranean area) species of acid soils, and the more far in the north they occure, the more concentration of calcium they need in the soil. Many of them have their northern limit in Sweden on Gotland, where the soil has a pH up to 9.5! So they can equivalent the missing temperature by a higher content of calcium. I think that you also can turn this point around: Species living on calcareous soil are also species which are thermophilic. So it should increase by global warming ....
Observations in my earlier home area, sw-Germany, this species did not show any changes in the last 30 years. It is a little bit increasing, because more roads were built in the Black Forest, which expands the available biotops, becuase those roads are always built by calcareous stones.
In Poland, Tremiscus helvelloides is a red list species of the highest category. This is due to the fact, that Poland has only very few areas which are calcareous and mountaineous at the same time. On this few sites no change has been observed in the last 20 years.

What concerns the ability to colonize new sites: I think the spores of fungi are "everywhere". So if there are favourable spots, they will be found. But I can imagine, that the concentration of Tremiscus spores is much lower at the margin of its distribution than in its center. So it is harder at the borders of a distribution area to hold its stand. That's why those marginal locations are often considered for conservation, even for species that are not so rare in other regions. For Tremiscus helvelloides it could well be that the northern border of the distribution runs through Great Britain. But I don't know.

best regards,
Andreas

[Dogghound]

Thanks alot Andreas, this information is greatly appreciated. Interestingly the population in question is in coniferous upland but not mountainous.

[mollisia]

Hallo,

how many meters above sealevel do you mean by "upland" and how far north in Great Britain does the location lay?

The distribution in sw-Germany is like this:

Vertikale Verbreitung: Kollin bis eumontan.
<90-200 201-400 401-600 601-800 801-1000 >1000
- 28 79 114 19 -

So, the speices is not strictly mountainous, as I said before, but occurs from appr. 270 m upwards, at locations which are demountainous at the foot of the higher areas.

best regards,
Andreas

[Chris Yeates]

hi I'm back but Internet links still v. dodgy

thankfully all the important stuff is backed up and also on newly acquired PC

further aspects of this very interesting theme are:

when we see / record a 'fungus' we are actually recording the fruiting body . . . do these fruitbodies appear when conditions are 'suitable' or actually when they are 'unsuitable'? to get anthropomorphic for a bit - if conditions for growth are perfect why does the fungus need to 'go' anywhere? is it only when the conditions are unsuitable that a fungus needs to produce spores to go elsewhere?

also - and Andreas will correct me if I go astray here - Fungal mycelia are typically haploid; i.e. they are not capable of producing fruitbodies in an area where only one spore has landed and germinated; they can grow and feed but not produce fruitbodies / and therefore sexual spores

I don't know what the sexual strategy of Tremiscus is, but this could be a limiting actor on its distribution - or rather its recordabledistribution

just because you can't see a fungus doesn't mean that it isn't there

try convincing planners with their greedy eyes on a site where a rare fungus was recorded a century ago that it is probably still there!!

cheers

Chris

[mollisia]

Hallo Chris, hallo all,

Originally Posted by Chris Yeates

when we see / record a 'fungus' we are actually recording the fruiting body . . . do these fruitbodies appear when conditions are 'suitable' or actually when they are 'unsuitable'? to get anthropomorphic for a bit - if conditions for growth are perfect why does the fungus need to 'go' anywhere? is it only when the conditions are unsuitable that a fungus needs to produce spores to go elsewhere?

I think that all organisms try to be as productive as they can. So when situations is favourable, all organisms will try to reproduce itself as muich as possible. So I would think, that when situation is perfect, a fungus always will produce reproductive units (however they look like) and not "calm down and have a rest".

But if a mycelium is rich on fruitbodies, can we be sure that this is a sign for the health of this mycelium? I don't think so. From trees e.g. we know, that just when they are in a dangerous situation for staying alive, they produce a last overwhelming mass of seeds. This is known from conifers as well as from beech and oak. So why not from fungi?
May be the location rich of fruitbody is a sign of a perfect situation, but also may be it's a sign of a last try to survife?
From cultures of fungi it is evident, that a disrupture of the mycelium results in a higher production of fruitbodies. Whether this is also true for mycelia in nature, which are under the pressure of concurating species, we don't know. Sites in my area which are often "destroyed" by wild hogs are nevertheless rich in (mycorrhizal) fungi. So inspite that areas look like some tanks have had a funny time there, are still or even more productive of fruitbodies. Not only one year, but for many years. So in this case I would argue that it is not a "last try" of the mycelium, but that the situation for it is favourable. May be the hogs destroying the upper layer of the soil reduce the concurating organism and therefor support mycorrhizal fungi?

Fungal mycelia are typically haploid; i.e. they are not capable of producing fruitbodies in an area where only one spore has landed and germinated; they can grow and feed but not produce fruitbodies / and therefore sexual spores

To my knowledge this is correct for all fungi, at least the higher ones which we treat. I don't know the situation in rusts or yeasts or such kind of fungi.

I don't know what the sexual strategy of Tremiscus is, but this could be a limiting actor on its distribution - or rather its recordabledistribution

just because you can't see a fungus doesn't mean that it isn't there

try convincing planners with their greedy eyes on a site where a rare fungus was recorded a century ago that it is probably still there!!

Perfectly true, although a century is perhaps a little too much. But at least 30 years or so it is in the experience of people I know that a certain fungus (Gomphus clavatus in one case) was not recorded at a very place and then was again producing fruitbodies. But in theorie one could also argue, that the mycelium was NOT there in the meantime and the re-appearance is due to a new colonisation of the spot. I think this is unlikely, but you can not exclude that nevertheless.

This is also a problem for creating red lists. May be there are fungi which are capable of living in a mycelium state or in an imperfect state (not know to us perhaps) for many years and possibly live in this state "everywhere", but fruitbodies are only seldom seen. Is this a rare fungus? Of course not, only the fruitbodies are rarely produced. That may have reasons which we don't know.
An example to illustrate this is e.g. Oligoporus ptychogaster and its anamorphe Ptychogaster fuliginosus. The anamorph is very common, but the teleomorphe is very rare. If we wouldn't know, that these two states are the same species, we would probably put the teleomorphe on a red list.


For the red list of fungi in sw-Germany I have only very sparsingly used the category EX (extinct). It is used in the case that:
1. The species is not recorded in the last 50 years (1957 backwards, in a few spectaculare cases 1960 backwards) and
2. It is a species which is not very likely to be overlooked and
3. It has been made effort to re-search the species on the former known location

exceptions from 1. have been made in cases, where all known localities of a species has been destroyed completely (not only clearance of forest, but clearance and building streets or buildings on that place). So we had e.g. only one location of Boletus torosus, which was observed for appr 10 years or so. Then the forestry path where this species was growing was broadened to build a road for trucks, the symbiontic tree the mycelium was living with has been felled. This location is with certainty destroyed and therefore B. torosus is classified in category 0, which means "extinct or probably so". May be once another location will be found, then the category has to be changed. Red lists are no static publications for eternity anyway ....

best regards,
Andreas

[Dogghound]

The site is around 190m above sea level Andreas. The highest point in the same national park is 370m above sea level. So it about fits in this respect. Its in the North Yorkshire moors im not sure what scale this is.

Very interesting points chris. I never really thought avbout the fact its only the fruiting body that is visible.