Lichens of Wales

Arthonia atlantica

Description & Identification

 Hard acid rocks in dry underhangs and sheltered sides of old walls, usually near the coast.


 SW England, W Scotland, W Ireland and W Wales. Outside the British Isles known only from Brittany.

Records from Wales
Location Grid Reference Last Rec'd Recorder SSSI
Cardigan: Coedmor NNR SN14, SN24 1996 A. Orange & P. Wolseley Yes
Caernarfon: Nantgwynant SH65 1973 A. Pentecost Yes
Meirionydd: Porthmadog SH58274107 2002 A. Orange No
Pembroke: Skomer Island - North Castle SM7305 1750-1996 Unknown Yes
Radnor: Coed Aberedw SO0747 1960 Unknown Yes


Notes on individual locations

Skomer Island - surveyed by Natural History Museum lichenologists in the mid-1990s, but this species not recorded.

Coed Aberedw - the record in the Welsh Threatened Lichen database puts this site in Ceredigion. But there is no site of this name in this vc and the grid-ref places the record in the Radnor site. This inland site is anomalous however.

Coedmor - occasional on rock outcrops in NNR compartments 2,6,9,10 and 11. 

Porthmadog - Pen y Garn, Prenteg. On rocks below overhang in Quercus petraea woodland.

Proposed Actions

UKBAP Signposting Actions:


Monitor the habitat and species at two extant sites, at least every 6 years, to ensure that management maintains or expands woodland continuity and modify accordingly. Pay special attention to threats from excessive shade cast by climbers, and evergreen trees and shrubs, particularly invasive non-native species, and inappropriate grazing levels and forestry operations.


Promote agri-environment schemes capable of delivering appropriate site management.
Hectad Distribution in Wales/Link to NBN Gateway Map

NBN Taxon Key