Peltigera elisabethae
An attractive montane calcicole Dogtooth, mainly recorded from the Breadalbane hills, but with a few records from elsewhere. Similar to Peltigera horizontalis, including horizontal apothecia (but these have not yet been seen in Britain), but with a very different underside and often has marginal schizidia. The lower surface is dark brown-black, with a distinct paler margin, without veins but with small, starkly white interstices centrally. There are very few post 2000 records, which likely reflects the lack of recent recording in montane habitats, but with climate change threats, this is a matter of concern.
Thallus 10–15 cm diam., lobes 1.5–2 cm broad and to 5 cm long; upper surface grey-brown, metallic-shiny, with pale slash-like cracks (as in P. neckeri), peeling near the margins to form lobulate crisped and curled isidioid schizidia and lobules; medulla thick; lower surface dark brown-black, paler near the margins, without veins but with small, starkly white interstices centrally; rhizines dark, fasciculate, rather thick, concentrically arranged as if in annual rings. Apothecia rare (not observed in British material), horizontal, with a flat rounded or oval disc as in P. horizontalis. Ascospores 25–45 × 3–7 µm, 3-septate. Thallus with tenuiorin, methyl gyrophorate, gyrophoric acid (C+ red), T3 and ± T4, and unidentified terpenoids.
Characterised by the thick thallus, crisped marginal schizidia and the non-veined felted dark underside with only scattered, pale interstices. Peltigera horizontalis has very distinct anastomosing dark veins and entire margins to the lobes.
On mossy rocks over 700m, but in the Ochil Hills at a considerably lower altitude.
Rare, Scottish Highlands and Wales (Snowdonia).
A montane calcicole lichen, mainly recorded from the Breadalbane hills, but with outlying records for Caenlochan, Agnus, a low lying gorge in Alva Glen in the Ochil Hills and Snowdonia, North Wales. There are very few post 2000 records, which likely reflects the lack of recent recording in montane habitats, but with climate change threats it a matter of concern that this species is not being adequately monitored.
Britain: Near Threatened
Scotland: Priority Taxon for Biodiversity in Scotland
Wales: Near Threatened
Cannon, P., Magain, N., Sérusiaux, E., Yahr, R., Coppins, B., Sanderson, N. & Simkin, J. (2021). Peltigerales: Peltigeraceae, including the genera Crocodia, Lobaria, Lobarina, Nephroma, Peltigera, Pseudocyphellaria, Ricasolia, Solorina and Sticta. Revisions of British and Irish Lichens 20: 1-34.
Text by Neil A Sanderson based on Cannon et al (2021)