Wednesday, 7 October 2015

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

Tuesday, 6 October 2015

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
K+ yellow
No isidia

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
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

Monday, 5 October 2015

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

Tuesday, 22 September 2015

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

Wednesday, 16 September 2015

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

Friday, 4 September 2015

Oxyrrhynchium hians

Oxyrrhynchium hians is a common pleurocarp which can be identified quite readily with care and a good hand lens in the field. With the example below I could see through the hand lens the nerve extending past the half way mark but not reaching the tip and the margin of the leaf toothed. A good feature for O.hians is the leaves being spaced out along the stem.

Oxyrrhynchium hians leaf

Oxyrrhynchium hians

Sunday, 30 August 2015

Woolly Fringe-moss - Racomitrium lanuginosum

Found on Dartmoor this common species is quite forward to identify. Under the microscope the long wavy cells identify the group as Racomitrium. Grimmia also has wavy cells but these are short. Racomitrium lanuginosum has 90 degree projections on the white hair point which is visible with a high powered magnifying glass.

Racomitrium lanuginosum

Racomitrium lanuginosum long wavy cells

Racomitrium lanuginosum close up of hair point

Tuesday, 25 August 2015

Cerastium pumilum - Dwarf Mouse-ear

Cerastium pumilum and Cerastium semidecandrum are similar with the bracts being the best feature to separate the two. C. pumilum has a narrow translucent border and C. semidecandrum has a much larger translucent area.

Cerastium pumilum

Cerastium pumilum bract

Polygonum aviculare - Knotgrass

I found this plant today which I knew was Knotgrass but thought it would be fun to find out which. As it turned out it was rather more difficult than I imagined. It was the key in Stace that got me to the conclusion in the end by the 3mm length of the achene (dry fruit of a flowering plant). There was a mention of silvery sheaths later turning brownish in Domino Guides which I could see. Polygonum arenastrum (Equal-leaved Knotgrass) is the one I had most trouble with. P.arenastrum is said to have leaves on the stem and branches roughly the same but the leaves on the stem were different sizes making this feature difficult to determine. Maximum size of achene on P.arenastrum is said to be 2.5mm therefore not my plant.

Polygonum aviculare achene 3mm in length

Polygonum aviculare

Monday, 10 August 2015

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

Cystiphora sonchi

This gall was found on a basal rosette of Sonchus in a coastal dune at Wall Common, Somerset. The galls are very distinctive and examining through the microscope I could see the little diptera larvae.

Cystiphora sonchi larva

Cystiphora sonchi gall

Wednesday, 5 August 2015

Charmouth 1st August

I spent the morning near Charmouth looking for some local specialities namely Slender Centaury, Cliff Tiger Beetle and Sea Heath. To my delight I managed to find all three and some additions too. Being a beginner I found the Centaury group a little tricky to get the hand of but pointers that helped included looking for the presence of a basal rosette, whether the branches along the whole stem or just the top half and the leaf shape.

Lesser Centaury

Sea Heath

Slender Centaury

Asaphidion pallipes

Cliff Tiger Beetle

Stagonospora atriplicis

Thursday, 30 July 2015

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

Wednesday, 15 July 2015

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

Tuesday, 9 June 2015

Coleophora albicosta

A relatively straight forward Coleophora trapped in the New Forest on 5th June. There are a few Coleophora's with white lines along the forewings but the genitalia plate confirms to species level.

Coleophora albicosta genitalia plate

Coleophora albicosta

Tachypeza nubila

Found at night scuttling around on tree trunks and reluctant to fly. A member of the hybotidae family this I believe is Tachypeza nubila.

Tachypeza nubila

Aulagromyza hendeliana?

Couldn't get to species level with certainty as this was a female but it seemed to key out quite well for Aulagromyza hendeliana. Lack of photographic material of the adult also hampered a certain conclusive ID. The wing venation, size (2.75mm), mesonotum colour and yellow knees were useful pointers in this case.