KEYS TO THE LICHENS OF ITALY - 44) GRAPHIS and PHAEOGRAPHIS
This key includes all species of Graphis and Phaeographis which are known to occur in Italy (Nimis 2016), for a total of 9 species.
The phylogeny of Graphidaceae has been elucidated by Rivas Plata & al. (2013). The large (c. 450 species), mainly tropical genus Graphis was thought to have very few representatives in Europe, the most common and widespread of which was G. scripta, an extremely variable lichen: on the same trunk one can often distinguish among several individual, never merging thalli, just on the base of the shape and form of the ascomata. Neuwirth & Aptroot (2011) have proposed a new taxonomy for G. scripta s.lat., recognizing four distinct taxa: G. betulina, G. macrocarpa, G. pulverulenta, and G. scripta s.str. However, a more recent study based on both molecular and morphological characters (Kraichak & al. 2015) showed that, although between six and seven putative species are nested within the complex, these do not fully correspond to the taxa that were recently distinguished based on apothecium morphology, and cannot be circumscribed with the morphological characters that were traditionally used in the classification of the complex. Any formal taxonomic treatment will require additional sampling and evaluation of additional traits that potentially can characterize these clades. Pending further studies, I adopt here the morphological subdivision proposed by Neuwirth & Aptroot (2011), warning that the Italian distribution of the segregate ‘species’ is still very poorly known.
Rivas-Plata & al. (2013) have shown that the genus Phaeographis is polyphyletic: Phaeographis s.str. thus far appears to be restricted to the type species, Ph. dendritica, which is characterised by a white, ecorticate thallus and epruinose ascomata. Most of the c. 180 species of Phaeographis s.lat. have a corticate thallus and pruinose ascomata, and the name Ectographis is potentially available for these. However, many more species need to be sequenced to establish a solid phylogeny and generic concept for Phaeographis and its allies. The 3 species known to occur in Italy are all rare, and bound to warm-humid situations, which reflects the mainly tropical distribution of the genus.
Kraichak E., Lücking R., Aptroot A., Beck 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). Org. Divers. Evol., 15, 3: 447-458.
Nimis P.L. 2016. The lichens of Italy. A second annotated catalogue. EUT, Trieste, 740 pp.
Neuwirth G, Aptroot A. 2011. Recognition of four morphologically distinct species in the Graphis scripta complex in Europe. Herzogia, 24, 2: 207-230.
Rivas Plata E., Lumbsch H.T., Lücking R. 2012. A new classification for the lichen family Graphidaceae s.lat. (Ascomycota: Lecanoromycetes: Ostropales). Fungal Divers., 52: 107-121.
Rivas Plata E., Parnmen S., Staiger B., Mangold A., Frisch A., Weerakoon G., Hernandez J.E., Caceres M.E.S., Kalb K., Sipman H.J.M., Common R.S., Nelsen M.P., Lücking R., Lumbsch H.T. 2013. A molecular phylogeny of Graphidaceae (Ascomycota, Lecanoromycetes, Ostropales) including 428 species. MycoKeys, 6: 55-94.