Tuesday 21 May
Lichen (Caloplaca aractina)
What’s the World’s Favourite Species?Find out here.
Lichen fact file
- Find out more
- Print factsheet
Caloplaca aractina is a 'crustose' lichen; one with a crusty-like appearance. The body of the lichen (its thallus) is an oily dark brown to grey colour, which means it can be overlooked against the rock on which it grows. The fruiting bodies are slightly more obvious when they appear, being orangey-brown in colour, sometimes bright red though very small (less than 1mm).
- Patch diameter: several cm.
Lichens have colonised some very extreme habitats, including some of the coldest and hottest areas of the planet. They are incredibly hardy organisms, able to survive for years on the minimum of water, and growing almost imperceptibly slowly. If you examine the colonies that grow on tombstones, you can work out the age of some of these patches of lichen. Tombstones usually have a date on them revealing the year that the bare stone became available for colonisation.Top
In the UK, the range of this lichen is limited to the Lizard Peninsular, Cornwall where it is quite frequent on coastal rocks. There are other records from the British Isles but these are now believed to be incorrect. It is also found along the coasts of western Europe and from inland southern Europe.Top
This lichen likes sloping rocks, up to 100 metres above high water mark. On the Lizard Peninsular, it is always on serpentine rock. Elsewhere, it seems to prefer silica-rich rocks.Top
Classified as Critically Endangered in the UK.Top
This species is not currently threatened, though it may be vulnerable to oil spill incidents on some of its sites. It is not fully understood why this species has declined so drastically over the last fifty years. Scrub encroachment might prove a threat at its only known site in the UK.Top
Caloplaca aractina is listed in the UK Biodiversity Action Plans and included in English Nature's Species Recovery Programme. The site on the Lizard where it is found is a National Nature Reserve, so appropriate management for the species does not pose a problem. However, with a species that has such a precarious status in Britain, it is important to find out as much as possible about its requirements. It is necessary, too, to make mycologists (fungi experts) aware of this species and encourage them to report any sightings of the lichen elsewhere. Part of the Species Action Plan for C. aractina is to compile a list of suitable sites to search for the lichen, and compile a database of endangered lichens. This might help other members of this fascinating group that are critically endangered.Top
Information supplied by English Nature.
- Type of simple plant body that does not have stems, leaves and roots.
More »Related species
Play the Team WILD game
MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite ARKive images and videos and share them with friends.
Terms and Conditions of Use of Materials
Copyright in this website and materials contained on this website (Material) belongs to Wildscreen or its licensors.
Visitors to this website (End Users) are entitled to:
- view the contents of, and Material on, the website;
- download and retain copies of the Material on their personal systems in digital form in low resolution for their own personal use;
- teachers, lecturers and students may incorporate the Material in their educational material (including, but not limited to, their lesson plans, presentations, worksheets and projects) in hard copy and digital format for use within a registered educational establishment, provided that the integrity of the Material is maintained and that copyright ownership and authorship is appropriately acknowledged by the End User.
End Users shall not copy or otherwise extract, alter or manipulate Material other than as permitted in these Terms and Conditions of Use of Materials.
Additional use of flagged material
Green flagged material
Certain Material on this website (Licence 4 Material) displays a green flag next to the Material and is available for not-for-profit conservation or educational use. This material may be used by End Users, who are individuals or organisations that are in our opinion not-for-profit, for their not-for-profit conservation or not-for-profit educational purposes. Low resolution, watermarked images may be copied from this website by such End Users for such purposes. If you require high resolution or non-watermarked versions of the Material, please contact Wildscreen with details of your proposed use.
Creative commons material
Certain Material on this website has been licensed to Wildscreen under a Creative Commons Licence. These images are clearly marked with the Creative Commons buttons and may be used by End Users only in the way allowed by the specific Creative Commons Licence under which they have been submitted. Please see http://creativecommons.org for details.
Any other use
Please contact the copyright owners directly (copyright and contact details are shown for each media item) to negotiate terms and conditions for any use of Material other than those expressly permitted above. Please note that many of the contributors to ARKive are commercial operators and may request a fee for such use.
Save as permitted above, no person or organisation is permitted to incorporate any copyright material from this website into any other work or publication in any format (this includes but is not limited to: websites, Apps, CDs, DVDs, intranets, extranets, signage, digital communications or on printed materials for external or other distribution). Use of the Material for promotional, administrative or for-profit purposes is not permitted.