Butcher's Wood is a Woodland Trust Wood located in an Area of Outstanding Natural Beauty. It's an ancient oak woodland, complimented by hazel, bluebells and a huge range of epiphytes (organism that grows on the surface of a plants) that are found in the temperate zone woods (e.g. many mosses, liverworts, lichens, and algae).
I visited with a local lichenologist who is kindly teaching me lichen identification skills.
The first lichen we focussed on was this crustose Pyrrhospora quernea
Crustose lichens are lichens that form a crust which strongly adheres to the substrate (an oak in this case).
We identified it using the key in F.S. Dobson's A Field Key to Lichens on Trees (2013), following a tree of decisions based on morphological characteristics, colour and chemical spot tests.
Pyrrhospora quernea
The red 'dots' in this photo are red apothecia. The orange patch is the result of the sodium hypochlorite spot test (C test) - positive, area turned orange in response to sodium hypochlorite. The lower light green patch is a negative response to the potassium hydroxide (P test); negative, no colour change - just "darker" grey-green because the thallus was wet
Here is the account of this genus and species in F.S. Dobson Lichens: An illustrated Guide to the British and Irish Species (2018)Genus: Pyrrhospora
('fire-red spores' from the colour of the apothecia [one type of fruiting structure produced by the fungal component of the lichen. An apothecium is cup- or disc-shaped ... and contains the spores, which allow for sexual reproduction]
Thallus [the lichen body, which contains both a fungal and algal (photobiont)
component] crustose. Photobiont [the photosynthetic component of a lichen, either green algae or cyanobacteria, located beneath the cortex] trebouxioid. Apothecia lecideine [apothecia having thalline margin [outer rim found in lacanorine apothecia containing both algal and fungal cells]]. Paraphyses [sterile filaments growing between the asci] often slightly branched and not having swollen tips. Ascus [bag like structure containing the spores] 8-spored, Lecanora- type. Spores simple, colourless, but pale brown when over-mature.
K/I reaction to ascus tip.
Pyrrhospora quernea
Thallus thick, ochre to greenish fawn, consisting of granular soredia [small powdery propagule containing a few algal cells and fungal hyphae]. It is frequently surrounded by a black prothallus [area around edge of a crustose thallus which does not contain algal cells]. Sometimes described as having the texture of a miniature deep pile carpet. Usually infertile or with numerous small (up to about 1 mm wide), purplish to red-brown, irregular-shaped, very convex apothecia which darken with age and appear almost as if they are melting. Spores 8-12 x 5-7 um. When infertile it may be confused with Lecanora expallens but that species has finer, less buff, more green- yellow soredia and often a grey, fimbriate prothallus. Pertusaria flavida is isidiate. [i.e. having insidia, structures that projects from the thallus and contains both fungal and algal components. An isidia can detach from thallus and therefore serves in vegetative reproduction.] KC+
Habitat: Frequent on well-lit to lightly shaded, rather nutrient-rich, rough-barked orange, C+ orange, UV+ orange. trees, especially oaks, in 'old forest' situations. Also occurs on the sides of old Sandstone gravestones. It is rarer in the North.
The definitions of terms found in square brackets [] are either from the (a) Wisconsin Department of Natural Resources Glossary of Common Lichen Terms
or (b) the glossary in Dobson (2018)
Lecidella elarochroma
Identification:
Thallus is yellow grey to green grey, smooth to slightly granular often limited by a black line when it meets other lichens. Frequently found in mosaics, especially with Lecanora species. Usually fertile with black apothecia about 1 mm in
diameter which become convex with excluded margins.
Chemistry:
Thallus: C+ orange (sometimes a weak reaction, especially in the shade,
K+ yellow, KC+ yellow, Pd --, UV+
Similar species:
Fuscidea lightfootii has a much rougher, warted surface and is C
Habitat:
Smooth barked trees, shrubs and fences.
Distribution:
Throughout British and Ireland.
Graphis scripta
Graphis genus lichens are crustose and are called graphis because they look like writing. Graphis scripta is sometimes called Script Lichen, or Secret Writing Lichen
Identification:
Thallus crustose, white to grey, smooth or wrinkled. Apothecia very variable,
elongate, curved or branched with raised, unfurrowed , lip like black margins. The centres of these lirellae are often open and are then covered in white crystals.
Chemistry:
K -, P
Similar species:
Graphis elegans is similar but with a yellowish tinge to the thallus. The lirellae are usually shorted and the margins of the elongate apothecia are furrowed, although this can be hard to see. Its chemistry is K+ yellow turning blood red, P+ orange.
Habitat:
Very common on smooth barked trees, especially hazel, also on
heather stems and twigs.
Distribution:
Throughout Britain and Ireland but more frequent in the west.
Lichenicolous fungi
Pertusaria pertusa, "Pepper Pot Lichen"
Identification:
A crustose lichen. Thallus greenish grey to grey, thick and slightly cracked, often
limited by a prothallus and with a concentrically zoned margin. Apothecia are produced in wart like protuberances (up to about 2mm diameter). Each
wart has two seven apothecia with discs appearing as minute dark pits.
Chemistry:
Cortex K+ yellow, KC+ yellow, P+ deep orange, UV + orange
Habitat:
Common on trees. Sometimes on siliceous rocks, memorials and walls.
Distribution:
Throughout Britain and Ireland
Parmotrema perlatum
Photos shows the underside with rhzines visible, and the cilia round the margin of the lobes
Identification:
Thallus light pearl grey, orbicular, up to 15cm diameter. Lobes smooth, to 8mm wide, with ascending, incised and undulating margins which have soralia [structures producing soredia] along the margins. Black cilia, up to 2mm long are often found along the margin.
Lower surface black with simple rhizines [structures securing the lichen to the substrate], tan towards the margins which are often devoid of rhizines . Rarely fertile; apothecia with partially sorediate margins.
Chemistry:
Medulla [the inner part of the thallus lacking algae, usually of loosely packed fungal hyphae [long, branching, filamentous structure of a fungus]] and soralia : K+ yellow, P+ orange, KC+ yellow orange, UV
Similar species:
P. crinitum is isidiate with cilia on the surface rather than along the margins.
P. reticulatum has soredia on the tips of narrow upturned lobes and a K+ red medulla.
Habitat:
Common on trees and rocks.
Distribution:
Widespread in the south and west but becoming rarer northwards.
This bryophyte (a liverwort) was on the oak tree with the Parmotrema perlatum; it is Frullania dilatata, Dilated Scalewort
Flavoparmelia soredians
Red spot is the result of the potassium hydroxide spot test: turned red
Growth type foliose.
Photos: On urban trees. Co. Cork, SW Ireland.
Very similar to F. caperata but has a smaller thallus narrower and more adpressed lobes. Soredia is powdery rather than granular. Apothecia are rare but usually contain mature spores.
Occurs on well-lit, often dusty trees, fences, roofs, rocks. Range seems to be increasing as pollution levels drop.
Luffia lapidella, Gray Bagworm moth - lava
in/on a leprose-crustose lichen (probably a Lepraria sp. ("dust") lichen) on an ancient broadleaf tree. The lava was covered in soredia (minute dusty aggregations of the lichen's fungal hyphae and their photobiont, normally alga, which photosynthesises sugars that their fungal partners need) as it was eating soredia. The lava inadvertently spreads the soredia to start "new" patches of the lichen, which is one of the ways that asexual lichens reproduce - the soredia can also be spread by wind or rain as well as a range of animals.
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I am grateful to receive corrections if I have made an identification error.