Saturday, February 17, 2007

A slime mould (nee fungus) on the birdtable

POST-PUBLICATION UPDATE: As readers will see from the comments appended to this post, I'm inclined now to think that what I call a 'fungus' in the posting below is in fact the slime mould (myxomycete) Lycogala epidendrum.

Given my status as an untrained amateur, it has always been inevitable that during my mission to identify all the living things in my garden life I would meet things that stump me. Today's post marks one.

I have an old wooden bird table in my garden. Growing along one edge is the fungus seen in photo 1 (click on it to enlarge).

In a blatant display of plagiarism (see here !) I'd be pleased if any reader can "Name That Mushroom!"

The fungal bodies are small (~1-5 mm) 'blobs' that lack any obvious sign of a structure (stalks, cups etc.) under a hand lens. Until recently they were a more vivid red/orange. Old age and recent bout of snow has left them past their best.

Under the microscope the fungal mycelia are clear (photo 2, 1000x, 1 small division=1micron) . (For anyone reading not familiar with fungi: the mycelia are the 'spaghetti-like' threads. These make up the body of the fungus).

I am not at all expert on the microscopic caracterisitics of fungi, but I think the mycelia are uniseptate (again, for the unfamiliar: looking on the photo just above "7.5" on the graticule, you'll see a thin cross wall - a 'septum' - in the mycelial thread). There was no obvious blue reaction with Melzer's reagant.

A further puzzle is that despite a considerable time spent carefully scanning samples under the microscope I failed to find a single spore or ascus (='tube' full of spores). I am used to seeing large numbers of spores if ever I view larger, more familiar mushrooms. I'm not sure whether my failure to find any in this case is due to there being a greater skill/element of timing in finding them for the smaller fungi, or whether it is that I'm not correctly interpreting what I am seeing. I read, for example, that some smaller fungi spread by 'thallic conidiogenesis' (see here for some nice animations illustrating what this means). For all I know, maybe this is happening and perhaps even visible in the photo to the experts out there.


Laura said...

My guess is that we're talking Myxomycetes or slime mould. A rather curious group neither quite fungi or quite animal. Try here for good information and look at Lycogala epidendrum. Looks kinda similar on a microscopic level...What do you think?

Henry Walloon said...


Thank you!

Having spent some time searching the internet for images of slime moulds (Lycogala epidendrum in particular) I'm certain you're right.

A slight puzzle for me is that from images of slime mould 'mycelia' (or 'capillitia' as I've learnt to call them today), it seems that they are quite often heavily textured (that of L. epidendrum gets described as 'wrinkled') and I struggle to make mine out as anything other than smooth...but then mine is a budget microscope on the limits of its magnification!

Suffice to say: please award yourself ten Brownie points!


Laura said...

The points are all yours, Henry!