Caloplaca aurantia

Found on a gravestone at my local churchyard, the lemon shaped spores on this Caloplaca narrow down to aurantia, thallincola and flavescens. All three look different visually so identification is straight forward here.

Caloplaca aurantia lemon shaped spore

Caloplaca aurantia

Xanthoria parietina

Perhaps one of the most common lichens and sometimes useful to separate with other Xanthoria's such as polycarpa under the microscope as the spores are very different.

Xanthoria parietina section

Xanthoria parietina spores

Xanthoria parietina

Protoblastenia rupestris

Found in my local churchyard this lichen is easily identified as Protoblastenia by the apothecia and the K+ crimson reaction to the apothecia. Spores measured up to 10x7.5µm
Identification made by apothecia only up to .5mm, K+ crimson reaction and the spores elipsoid rather than globose.

Protoblastenia rupestris section showing K+ reaction

Protoblastenia rupestris spores

Protoblastenia rupestris

Lecanora conizaeoides

A slightly unusual form of Lecanora conizaeoides as the apothecia borders aren't clearly visible. It does still come out as this species when examined under the microscope as far as I can tell.

Edit: I re-examined this lichen after seeing Ochrolechia androgyna which looks very similar to me. The spore size confirmed that this is L.conizaeoides.

Lecanora conizaeoides

Lecanora conizaeoides section

Lecanora conizaeoides section after K added

Lecanora conizaeoides spore

Lecidella elaeochroma

Here's a common lichen found on a Yew tree in Somerset. All three apothecia are from the same lichen. The section shows that the lichen is Lecideine and the KI+ reaction with lecanorine shape reaction narrows down to three groups of which only Lecidella is found on wood. Within the Lecidella group Lecidella looks to be the only species found on wood.

Lecidella elaeochroma ascus

Lecidella elaeochroma section

Lecidella elaeochroma spore

Lecidella elaeochroma

Opegrapha prosodea

My third Opegrapha under the microscope today. This one found on a Yew tree in Somerset. It keyed out well for Opegrapha prosodea:

• Photobiont present
• Thallus without soredia and apothecia present
• Ascospore 12-septate
• Apothecia remaining slit like
• Apothecia 1-3mm long and ascospores 52.5µm x 7.5µm

Opegrapha prosodea

Opegrapha prosodea spore 12-septate 52.5µm long

Opegrapha prosodea

Acrocordia conoidea

Found on a gravestone in Somerset this lichen was narrowed down to Acrocordia  by habitat, spore and physical characters. Here's a key for Acrocordia on stone:

1 perithecia up to 2mm - A. salweyi
- apothecia up to 1mm - 2

2 Perithecia 0.4-0.7µm - A.subglobosa
- Apothecia larger, up to 1mm - 3

3 Spores 10-20µm x 6-9µm - A.conoidea
- Spores 19-26µm x 9-12µm - A.macrospora

Acrocordia conoidea spore 19µm long

Acrocordia conoidea