Six of us piled into a taxi - row of three facing row of three - good for talking - and were driven to the park where we met the other four lichenologists.
Lichenologists returning on the far left |
THIS Account IS CURRENTLY A DRAFT ACCOUNT, and only half written, - whilst I await comments on identification of one or two species by more experienced participants, and find time to write up the second half..
I recorded 47 species - 14 of which were new for me.
- This is mostly because I come from the north of England so was pleased to see species that are more common in the south..
- and also because I now have the Seventh edition of Frank Dobson's book, (2018) rather than just the Fifth (2005) . (In the 2005 edition, He says he covers nearly 850 species out of the 1800 species so far recognised in Britain. In 2018 he says he covers more than 1000 species of the 2000 species so far recongnised in Britain.) !!!
- but mostly because there were experts who could tell me what the species are.
(Ah! 110 reported by Friday 1 Feb !!)
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The Day
Paul Cannon tells us that only one lichen record had been sent in from the Park. There is lots of scope for new records! There is a possibility that a A3 road widening scheme will affect the far end of the park so he is keen that we should visit that part too in our walk.
We don't get far. The very first tree in the car park has good specimens of Punctelia subrudecta and Punctelia borreri. Borreri has whiter edges to the thallus (and is black on the undersurface of the thallus at the centre , and is much more abundant in the south of England).
These pictures are not always brilliant - and are presented in some cases just as evidence that I saw them. However for both species you can see the white lumps on the thallus (pseudocyphellae) which burst open to form soralia, and the farinose soredia come out.
Punctelia subrudecta (common all over England): Darker Grey. |
Punctelia borreri (found mostly in the south of UK) |
We cross a bridge onto an island |
On the soil near the shore is a Micaria. Any ideas which? |
On top of the island (and leading to the Grotto) are limestone arches. The rocks are oolitic limestone I was told and have been brought from Gloucestershire or Bath.
We find species that I would expect on limestone such as some of the species that dissolve holes (like verrucas) for their reproductive bodies:-
e.g. Verrucaria baldensis except that it is not called Verrucaria any more, it is called Bagliettoa baldensis.
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Bagliettoa calceseda |
Lecanora crenulata grows on limestone |
Lecanora crenulata grows on limestone. The ascocarp border is crenulate and the surface of the ascocarp is pruinose (whitish) |
Caloplaca limonia: pale creamy yellow thallus: convex areoles covered in granular soriedia (C. limonea was just included in C citrina agg on Dobson 2005) |
The yellow is Caloplaca citrina (agg?) Not areolate. soredia diffuse. The green is Lecania erysibe - there is a closer version of this below: |
Thallus covered with blastidia which resemble minute granules but are formed in short sparsely branched chains forming a lyer typically 2 to 3 deep. and are green in well lit situaltions. Apothecia .3-.4mm diam with brown slightly conves discs and densley blastidiate margins. A blastidium is a globular propagule, containing mycobiont and photobiont, always produced by "budding" and frequently formed in series of two or more, with each new blastidium produced from the tip of the previous one. common on calcareous and nutrient enriched substrates in UK and lots in N and S England and in urban situations.
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Lepraria vouauxii |
Lecidella stigmatea -seen closer below |
Lecidella stigmatea - zoomed in. The thallus is areolate or cracked It is common on calcareous rocks. |
Acrodordia salweyi growing on the limestone. The fruiting bodies are like semicircular domes, (whereas Acrocordia conidea has cone shaped domes, and a pinker thallus) |
After this I went down into the Grotto.
There is a brick frames (which you cannot see) covered outside with the limestone and inside with crystals.
It was dark inside, except where daylight was allowed to stream through. Bu when a photograph is taken the gypsum and other crystals reflect the light.
There were two guides inside who told us about the history..
I listened awhile. Apparently Charles Hamilton ran out of money for building the grott. It was renovated and rebuilt just a few years ago.
.... Click here to find out about the afternoon lichen walk later..