Graphis persoonii
This is one of the two less common species of the Graphis scripta s. lat. group. It differs from G. scripta s. str. in its conspicuously open, dark brown, non-pruinose discs, rather short ascomata and a reduced thallus margin.
Thallus grey to brown, cracked, uneven. Ascomata straight, curved or branched; lirellae to 6 mm in length and 0.1–0.45 mm broad, with rounded or rarely with acute ends; young ascomata elliptical or rounded, mature lirellae elongate; discs exposed, non-pruinose, dark brown, shiny; thallus margin absent or appearing at the base of ascomata only; mostly erumpent, sometimes prominent and then with cracks along the base; true exciple 25–60 μm thick, black, the inner part frequently reddish brown. Ascospores 4–8 per ascus, 7- to 13- septate, 15–42 × 5–12 μm, the lumina irregular, elliptical or lentiform in section. Thallus mostly K–, sometimes K+ dirty reddish-brown.
This is one of the two less common species of the Graphis scripta s. lat. group. It differs from G. scripta s. str. in its conspicuously open, dark brown, non-pruinose discs, rather short ascomata and a reduced thallus margin. Referred to as Graphis macrocarpa (Pers.) Röhl. (1813) by Neuwirth & Aptroot (2011), but this combination appears not to exist.
Not yet clear, but has been found on Hazel in oceanic woodlands in the west and Holly in old growth Beech – Holly pasture woodland in the south.
No yet known, but appears rare, but possibly more oceanic than the other Graphis scripta s. lat. species. So far, recorded from The New Forest (Hampshire), The Vale of Ffestiniog (Merioneth) and Bonawe Woods (Argyllshire) (Neuwirth & Aptroot, 2011).
Aptroot, A., Weerakoon, G., Cannon, P., Coppins, B., Sanderson, N. & Simkin, J. (2023). Ostropales: Graphidaceae, including the genera Allographa, Clandestinotrema, Crutarndina, Diploschistes, Fissurina, Graphis, Leucodecton, Phaeographis, Schizotrema, Thelotrema and Topeliopsis. Revisions of British and Irish Lichens 36: 1-23.
Kraichak, E., Lücking, R., Aptroot, A., Dornes, P., John, V., Lendemer, J.C., Nelsen, M.P., Neuwirth, G., Nutakki, A., Parnmen, S., Sohrabi, M., Tønsberg, T. & Lumbsch, H.T. (2015). Hidden diversity in the morphologically variable script lichen (Graphis scripta) complex (Ascomycota, Ostropales, Graphidaceae). Organisms, Diversity and Evolution 15: 447-458.
Neuwirth, G. & Aptroot, A. (2011). Recognition of four morphologically distinct species in the Graphis scripta complex in Europe. Herzogia 24: 207–230.
Text by Neil A Sanderson based on Aptroot et al (2023)