Species: Lichen - unnamed 14 (Caloplaca austrocitrina)


Category: Fungi

Location: NW

A. Fungi

More extensive information on fungi can be found in a separate blog post.


There are more than 800 species of lichen in the Teloschistaceae family. Most of these lichens live on rock or bark.

NOTE: there are perhaps 120 families of lichen species. None of these have an English common name. We have therefore given them all the shared family name of ‘Lichens’. Although this is scientifically incorrect, it is better than saying something like ‘No English family name’. It also enables us to list all lichens on the search page by using this term.

C. Lichen - unnamed 14 (Caloplaca austrocitrina)

Caloplaca austrocitrina is a crustose type of lichen usually found on basic sandstone.

More information on this lichen species can be found on:

Additional Information

Lichens - background information

A lichen is not a single organism, but a collaboration between a fungus and another organism that is able to manufacture nutrients that the fungus cannot. This association is called symbiosis, and the fungus combines with an alga or a cyanobacterium, both of which produce nutrients by photosynthesis. This combination results in a body called a thallus. Each lichen has a unique fungus, whereas some algae and cyanobacteria enter into association with many different fungi, algae being the more common partner of the two. Lichens have different properties to those of the component organisms, and many different structures and colours. Lichens grow on many types of surface, and in a variety of environmental conditions, but are nutritionally self-contained so are not parasitic. When seen growing along the branches of a tree, for example, they are simply using the tree for support. They may be found growing in some of the most extreme habitats on the planet. Their names may be misleading; ‘reindeer moss’ is a lichen, and not related to mosses, which are non-flowering plants.

Lichens have many growth forms of the vegetative body parts, or fungal filaments, collectively called the thallus. These forms are:

  • fruticose (tiny, leafless branches)
  • foliose (flat, leaf-like structures)
  • crustose (crust-like flakes like peeling paint)
  • leprose (powdery appearance)
  • squamulose (tightly clustered, pebble-like forms)
  • filamentous (hair-like)

October 2023 Lichen survey - acknowledgements

We are grateful to Neil Sanderson and Dr. Paul Cannon of the British Lichen Society, who freely gave their time and expertise to conduct a survey of the lichens in Heene Cemetery on 9th October 2023. The species listed here was identified during this survey.


Lichen - unnamed 14 (Caloplaca austrocitrina)

Caloplaca austrocitrina is a crustose type of lichen usually found on basic sandstone.

[Because of the difficulty in photographing these small organisms, we have made an exception to our general rule of only using photographs that have been taken in Heene Cemetery. If and when we manage to take a photograph of this lichen, we will replace this royalty-free, stock image.]

(Photo credit: Mark Powell, showing "Flavoplaca (Caloplaca) austrocitrina, growing on copper-contaminated north wall of Riseley church, Bedfordshire. Material from this colony was analysed by Jan Vondrák in 2011 and it was found to belong to an unresolved clade, but later confirmed as a member of the genus Flavoplaca by Arup et al. (2014). The thallus is scarcely visible, if at all, and the fine blastidia usually appear as if arising directly from the substratum. F. austrocitrina has a bright chrome yellow colour. F. limonia has slightly larger and more 'plump' blastidia with a pale milky yellow colour. F. dichroa has similarly fine blastidia and may be difficult to separate when growing on vertical substrata (on which F. austrocitrina usually grows).", Creative Commons License.)