Showing posts with label Xanthoria parietina. Show all posts
Showing posts with label Xanthoria parietina. Show all posts

Monday, 19 November 2012

Smaller things

I was wondering how the queen bumblebee from October 28th was doing, and this morning we had a gap in the rain. Sure enough, at around 10 am, she was back at the Lavatera in the garden. (Well, I'm assuming it was the same one. Either we have two queens, each making a winter nest, or one queen working hard at getting her winter nest established. Either way, it's a notable observation.) I had hoped to follow her flight, but she went quite high and flew south so, sadly, her nest isn't all that close to me. It will be very interesting to see if we start to get B. terrestris workers in the next few weeks. Having said that, we had the first frost of the year last night. It was only a couple of degrees below, but a frost all the same. Here's a shot of the roof of my car:

Frost patterns

When the weather is on a bad run it's time to gather some samples and do some microscopy and deeper research.

There's a little mushroom that appears on my lawn several times a year. I know it's a Galerina, but today I decided to get it to species:

Galerina clavata
I put a specimen on a glass slide and waited overnight for a spore print. Here's the print on the slide waiting to be examined under the microscope:

Galerina spore print on the microscope
You can clearly see the brown spore print in that shot. (The blue column is the light shining up on the underside of the slide.)

We need to examine spores at a magnification of at least x400:

Galerina spores at x400

These spores are described as 'almond-shaped'.

I noted that the base of the stipe on the specimen was woolly white, so that makes it Galerina clavata, a common mushroom in association with mosses in lawns.

Liverworts are amongst our most overlooked plants. They are mostly tiny, and many could easily be assumed to be mosses. An in-situ shot would show nothing recognisable, so I took this shot (sample size about 3 cm. across) on paper in the study.

Liverwort sample about 3 cm. across
There doesn't seem much to work with there, but once you get a sample under the microscope, everything becomes clear. This sample is mounted on a slide ready for the microscope:

Liverwort sample on slide ready for microscopy
Note that the individual leaves have no central vein - a clear indication for a liverwort. There are no underleaves, and the leaves look to be entire, without lobes or teeth. Microscopy, however, reveals that the leaves are very slightly toothed - more so in the lower leaves - and that the teeth contain very few cells:


Cells in leaf tooth
All of this leads us to Plagiochila porelloides, which in this case is the predominant plant on the rear wall of the ditch where I found it.

I'm currently working on lichen microscopy. This is a specimen of Xanthoria parietina, an extremely common lichen that can be found on wood or stone and even on glass:

Xanthoria parietina
Lichens are an association between a fungus and a photobiont (either an alga or a cyanobacterium). Since the fungus is the only part of the organism that reproduces freely, I refuse to see this as symbiosis: I consider that the fungus (which needs the photobiont in order to survive) is virtually parasitic on the alga (which can and regularly does live happily on its own, without help from the fungus). This shot at x30 shows the circular cups which are the spore-producing, reproductive part of the fungus:

Fruit bodies of Xanthoria parietina

Wednesday, 24 November 2010

Seasonal images

We're expecting snow later in the week, and that kind of weather is often preceded by interesting morning skies. This is the view from my bedroom window this morning:

Croaghan Hill, 8am, 24/11/2010

Stormy weather had brought down some small branches, and I found this specimen of the lichen Xanthoria parietina:

The green and yellow cups look like tiny cup mushrooms, and that's exactly what they are: the reproductive components of lichens are controlled by the fungus. In this case the cups are purely fungal and produce only fungal spores. The spores are ejected to land some distance away and must land on the appropriate alga to form a new specimen of the lichen.

The Candle Snuff fungus - Xylaria hypoxylon -  grows on dead wood:


This nice little image of a Mycena growing in moss is tinged with more than a hint of sadness:

 
Mycenas are a tricky little group, and I'm sad to report that my friend and Mycena guru Gerry Shannon is no longer with us. He was a very jovial and enthusiastic mycologist who specialised in the LBJ's that we found. He will be sadly missed.