Parmotrema reticulatum

Always seem to struggle with foliose lichen so the best way to get good at them is to keep trying. First clues were with UV and chemical tests. There was a faint UV+ purple, C- and K+ yellow turning red. Visually the upper surface showed many fine cracks showing the white medulla and the underside was mainly black with brown lobe tips. The rhizines present are simple and fading towards the lobe margins but the lobe tips had some sparse simple rhizines. Overall this was enough information to key out this foliose lichen to Parmotrema reticulatum.

Parmotrema reticulatum underside of lobe

Parmotrema reticulatum upper side of lobe

Fuscidea lightfootii

Found this morning on a wooden gate. Only a single simple spore was found with 1µm epispore measuring 10x7.5µm not enough to to be certain of identity. If this was a typical spore then Lecidella elaeochroma f soralifera a contender but tests show it to be something else. The thallus was UV+ white and C- suggesting something more like perhaps Fuscidea lightfootii. However, when performing a second section on a younger looking apothecia I found multiple dumbel shaped spores which were typical of Fuscidea lightfootii measuring 8x3.5µm

Fuscidea lightfootii

Rhizocarpon lavatum?

It doesn't take much effort to determine a Rhizocarpon but getting to species level is a lot more difficult. This one wouldn't key out so I instead went with the closest match. No idea what the difference between muriform, submuriform and eumuriform is and no explanation in the book. Perhaps it would have been easier to reach an ID had I have known. I've put the details here to come back in time and re-evaluate:

Spores: muriform (or could be submuriform or eumuriform) 25x11.25µm turning brown when mature.
Ascus: 120µm
hypothecium: brown
hymenium: colourless
epithecium: brown
apothecia: 0.8mm
habitat: siliceous rocks near stream

Pos Rhizocarpon lavatum

Caloplaca from Brecon Beacons 25th March

Found on 25th March 2016 on a gate post this Caloplaca was not found to be identifiable with my level of expertise currently. A shortlist was drawn up using apothecia size (1mm) and habitat giving Caloplaca citrina as the best guess. Both the thallus and apothecia are K+ purple eliminating C. virescens and C.cerina. Apothecia colour elimnated herbidella. There were few polaricula spores the largest measured 15x4.5µm. Some of the paraphyses had swollen tips measuring 3.75µm

Lecanora pulicaris

Lecanorine apothecia up to 1mm
Thallus white crustose K+ yellow
Spores 15x7µm simple
Fine crystals extending from the epithecium into the hymenium seen with a polarizing filter.
Massive crystals in the exciple.

Lecanora pulicaris

Opegrapha sp. (vulgata)?

I've had to put this lichen down as Opegrapha sp. as it doesn't key out. I've put the information here so it can be referenced in the future should I get more information regarding missing species in current literature. Closest match would be O.vulgata but what looks like pycnidia is in fact the early stages of new lirellate.

Lirellate 1mm
Thallus endolithic with a greenish tint
No pycnidia, only newly formed lirellate resembling pycnidia.

Spores 5-septate 22x5µm
Ascus 42x12µm

Generic Key 5 p.57
True exciple present
Ascospore septate
Ascospore multiseptate
Ascospore lumina cuboid
Ascospore colourless
Lateral exciple in section brown-black
= Opegrapha or Lecanographa

Opegrapha key:
Photobiont present (not lichenicolous)
Thallus without soredia, apothecia present
Ascospore 5-septate
Apothecia disc remaining slit like
Ascospore 4-7 septate
On bark
Ascospore 4-9µm wide
Key end, no match.

Opegrapha's characteristics:
O.anomea - On Pertusaria amara
O.areniseda - Mainly coastal on soil and sand
O.atra - Clearly defined mosaic forming patches
O.brevis - On Thelotrema petractoides
O.calcarea - On rock
O.cesareensis - Coastal siliceous rocks
O.corticola - Sterile
O.demutata - White pruina
O.dolomitica - On calcareous schists
O.fumosa - Sterile
O.glaucomaria - On Lecanora rupicola
O.gyrocarpa - On siliceous rock
O.herbarum - Slit opening wide when mature
O.mougeotii - Limestone, mortar, calcareous sandstone
O.multipuncta - On small branches
O.niveoatra - Often sterile
O.ochrocheila - K+ magenta-red
O.parastica - On Aspicilia calcarea
O.paraxanthodes - Mainly upland deeply shaded rocks
O.pertusariicola - On Pertusaria leioplaca
O.physciaria - On Xanthoria parietina
O.prosodea - 50-70µm ascospores
O.pulvinata - On Dermatocarpon miniatum
O.rotunda - On Physconia distorta
O.rufescens - Apothecia .3 to .5mm
O.rupestris - On V.baldensis
O.saxigena - Deeply shaded siliceous rock
O.sorediifera - Sterile
O.sphaerophoricola - On Sphaerophorus globosus
O.subelevata - On limestone, mortar and sandstone
O.thelotrematis - On Thelotrema lepadinum
O.trochodes - Apothecia 0.15-0.4mm
O.varia -
O.vermicellifera - Similar to Lecanactis subabietina
O.viridis -
O.vulgata -
O.xerica -
O.zonata - Shaded siliceous rocks
O.zwackhii - On Phlyctis argena

Caloplaca citrina

1. Caloplaca saxicola
2. Diploicia canescens

No. 3
Thallus crustose-areolate
On basic rock
Thallus K+ purple

Again the K+ purple led to a Caloplaca species:

Thallus entirely sorediate
Thallus without any definite shape or form to the margins (see C.xantholyta)
Thallus yellow-green with distinct areoles often sparsely fertile

Caloplaca citrina

Diploicia canescens

1. Caloplaca saxicola

No. 2:
Infertile crust which is placodioid-lobate
Sorediate
K+ yellow
No isidia
C-

This one was quite easy and it ran through the key OK to this species with the above information. One that quickly becomes recognised by beginners.

Diploicia canescens

Caloplaca saxicola

I'm attempting to identify and list all the lichens in a local churchyard as a project to help me become more confident in identifying species in this group. This one is the first:

Pre microscopic clues:

Thallus yellow, crustose and lobed

Apothecia yellow, lecanorine and up to 1mm.

Apothecia K+ magenta

The above K+ magenta reaction suggests that the Lichen is Caloplaca or Protoblastenia.

Hymenium 100µm

Ascus 57x12µm

Spores 10x6µm and polaricular

Spores are colourless and simple with Protoblastenia which leaves us with just Caloplaca:

Thallus corticate (having a cortex)

On Rock

Cortex yellow K+ purple

Placodioid-lobate

Lobes less than 2mm, Ascospores ellipse shaped

Marginal lobes 2-5 times longer than wide with no blackening

Lobes 1mm or more

Lobes yellow with some white pruina, bloated, about 2x longer than wide on calcareous rock

Caloplaca saxicola

Caloplaca saxicola apothecia section

Caloplaca saxicola ascospore

Usnea subfloridana

Found about 10ft up on a tree trunk in the Forest of Dean this lichen took a bit of work to get a sample for identification:

Holdfast area blackened indicating it is either: U.flavocardia, U.fragilescens, U.subfloridana, U.silesiaca or U.wasmuthii.
Medula section is Compact not Lax ruling out U.flavocardia and U.fragilescens
This leaves us with three remaining Usnea's: subfloridana, silesiaca and wasmuthii. These three are difficult to separate in the infertile state. Had it been fertile then subfloridana would have been the favourite. As it is, the differences are down to the annual rings in the darkened holdfast. wasmuthii has regular annual rings whereas subfloridana has irregular. Wasmuthii is said to have a brickwork like pattern. Taking into account this pattern and the status and distribution we are left with Usnea subfloridana.

Usnea subfloridana

Usnea subfloridana isidiomorphs

Usnea subfloridana stem section

Physcia tribacia

When found on site it was suggested that this lichen was Physcia tribacia. I collected a sample and had a go at keying it out:
Getting to Physcia was achieved by the following characters:
Foliose lichen
Photobiont which is chlorococcoid (trebouxioid) and not cyanobacterial.
Lobes that are spreading rather than strap shaped and not hollow
Lobes lacking tomentum on the lower surface (felt like mat of fungal filament known as hyphae).
Whitish to pale grey coloured lobes with paler under surface, K+ yellow cortex, pseudoparenchymatous upper cortex (cell like structure formed by hyphae fusing together)

Getting to species level:
Lobes lacking marginal cilia (eliminating tenella and adscendens)
Soredia (fungal hyphae wrapped around a photobiont cell) developing on the underside of the lobe tips.
Lower cortex also pseudoparenchymatous.

Probable Physcia tribacia

Thallus section of probable Physcia tribacia

Toninia aromatica

I spent some time with this one and a had difficulty coming to a satisfactory conclusion. All the clues were giving me several options none of which seemed right at first but a photo of a Toninia following a saxicolous crack got me finally to the right group. Other groups considered were Catillaria, Cliostomum and Lecania. The reaction of K+ y put Cliostomum in the picture but it turned out to be a red herring. The spores are 17µm long and 3-septate. The paraphyses are with a swollen apex with pigmented tip.

Toninia aromatica

Rinodina bischoffii

A lichen that looks on first inspection to be lecanorine but the apothecia section shows it to be lecideine. The 16x11µm spores are quite distinctive so getting to Rinodina was quite easy.

Rinodina bischoffii

Rinodina bischoffii spores

Bilimbia lobulata

This is a lichen I re-examined and after several hours was glad I did as the outcome turned out to be different from the first. Description wise it's a granular thallus with black .75mm lecideine apothecia that are merging to create larger looking apothecia. It's growing on the top side of a brick wall. If you remove some of the lichen you can see that the underside is white. An apothecia section reveals 3-septate ascospores measuring 15µm x 4µm (too small for sabuletorum). The hymenium is brown measuring up to 90µm in height.

Bilimbia lobulata

Lichen Identifications

After spending a lot of the day examining lichens under the microscope I've discoverd a few that are new to me. Also below is a new one found yesterday on the southern slopes of Brean Down Toninia sedifolia with it's distinctive grey squamulose thallus and black contorted lecideine apothecia. Final lichen is one found at Cross Plain on a Hawthorn twig, Arthopyrenia analepta.

Toninia sedifolia

Arthopyrenia analepta

Brean Down 29th July

I've hardly been to Brean Down this year so thought it would be a nice change to have a look round and see what I could find. As it turned out there were a few discoveries of things new to me including: Weissia brachycarpa, Dermatocarpon miniatum, Ochesella villosa, Cryptocephalus fulvus and Squamapion atomarium.
I started off by examining the wall next to where I parked and found Bilimbia sabuletorum plus two bryophytes that looked like Ulota crispa and a Tortula sp. At the bottom of the steps I ran into Bugloss for the first time this year. This plant stood out with it's large prickly leaves and small blue solitary flowers. Half way up the steps I strayed on to the grass and instantly started to find some interesting things. Here I found the Weissia brachycarpa growing on soil on an overhang. The leaves were 1mm long and the old capsules still present which helped with the identification. I also found three Cryptocephalus fulvus in this area, a very striking beetle but very small so crawling round on hands and knees recommended. The crescent shaped gemmae cups weren't visible so perhaps not a feature to be looked for all year round.
Eventually I reached the top and made my way westwards but only managed a short distance before finding a new lichen, Dermatocarpon miniatum. This is a distinctive brown foliose lichen with lots of brown dots which I presume are the 0.3mm perithecia.
I also found here Black Meddick which intially gave me trouble identifying as I thought it was Clover to start with but the leaves end in a small point.

Black Meddick

Cryptocephalus fulvus

Weissia brachycarpa

Dermatocarpon miniatum

Lawrence Weston Moor and Blaise Castle

These two locations were visited on 14th July as they were both close to each other. First stop was Lawrence Weston Moor. It took some time to find some lichen but eventually added some 25 species to the list. First of interest was Melanelixia subaurifera. This species is similar to Melanelixia fuliginosa which needs examination of the isidia to tell them apart.
On the same tree was also saw a Parmelia. This group can be told by having white lines on the upper surface cracks of the thallus. On this occasion the Parmelia turned out to be sulcata.
Next was a lichen that looked at first glance like a Ramalina but examing the underside we could see it was a different colour looking more white which made it Evernia prunastri.
Just before leaving we met up with Mark Kitchen who had some plant specimens. I noticed a beetle on the Rumex which I later identified as Perapion curtirostre. Having the host plant was a useful ID feature in this case.
Later we went to Blaise Castle and walked parallel to a stream picking up some interesting lichens. Some are still to be determined but others could be named on site such as Pertusaria albescens which had a very distinctive prothallus. Caloplaca cerina was a nice find on the top side of a gate.
.

Caloplaca cerina

Pertusaria albescens

Punctelia jeckeri showing the pruinose lobes

Melanelixia subaurifera

Xanthoria elegans

Phaeographis dendritica

A surprise to see brown septate spores on this lichen under the microscope. Although a fairly common lichen it is not that easy to find in my county so a good record.

Phaeographis dendritica plus spore in inset

Fuscidea cyathoides

This lichen showed many spores that appear to be kidney shaped 11µm a characteristic of Fuscidea cyathoides. The ascus KI reaction I could see was fuscidea type but only after I knew what shape to look for.

Fuscidea cyathoides

Fuscidea kochiana

A straight forward identification for this one. Colourless 10x5µm spores turning brown when mature, swollen and pigmented cap of the paraphyses, fuscidea type ascus all useful characters.

Fuscidea kochiana KI ascus reaction

Fuscidea kochiana mature spores.

Fuscidea kochiana

Fuscidea kochiana