KEYS TO THE LICHENS OF ITALY - 42) OPEGRAPHA (with Alyxoria, Bactrospora, Cresponea, Enterographa, Gyrographa, Lecanactis, Lecanographa, Paralecanographa, Pseudoschismatomma, Psoronactis, Roccellographa, Syncesia, Zwackhia, and opegraphoid species of Arthonia)

Pier Luigi Nimis
Ertz & Tehler (2011) proposed a new phylogeny of several groups within the Arthoniales based on molecular data, together with important taxonomic implications. The molecular revision of the Arthoniales by Ertz & al. (2009) revealed the homoplastic nature of morphological characters traditionally used to circumscribe genera, such as exciple carbonisation and ascomatal structure. The genus Opegraphain the traditional circumscription appeared to be polyphyletic, its species being nested in all the major clades within Arthoniales. The transfer of Opegrapha atra and related species to Arthonia allowed the genus and the family Arthoniaceae to be recognised as monophyletic. Ertz & Tehler (2011) suggested a new phylogeny of several groups within the Arthoniales, together with important taxonomic implications, among which was the resurrection of the genus Alyxoria, to accommodate several species formerly included into Opegrapha. Finally, a molecular analysis of the family Roccellaceae by Ertz & al. (2014) has shown that several traditionally accepted genera, are para-/polyphyletic; in order to make these groups monophyletic, eight new genera were proposed, among which Gyrographa, to accommodate 2 species formerly included in Opegrapha, and Pseudoschismatomma for the Opegrapha rufescens group.
The following genera are included in this key:
Alyxoria - A segregate from Opegrapha presently assigned to the family Lecanographaceae. The molecular-based distinction between Alyxoria and Zwackhia is also supported by differences in the formation of the excipulum (Hillmann & al. 2016).
Bactrospora - This genus, characterised by cylindrical asci and acicular, multiseptate ascospores, and especially by the usual absence of hymenial gelatine, comprises several species formerly treated as members of Lecanactis. The genus, which includes c. 30 species, is widely distributed in tropical, subtropical and temperate regions of both Hemispheres and is tentatively included into the Opegraphaceae. A key to all known species has been published by Sobreira & al. (2015).
Cresponea - Cresponea resembles Lecanactis, differing in the epruinose margin of the rounded apothecia, the yellowish to reddish pruina on the apothecial disc, simple to sparsely branched, non-anastomosing paraphyses and ascospores with a conspicuous endospore. The genus, which belongs to the Opegraphaceae, is mainly tropical and includes c. 17 species. For further details see Egea & Torrente (1993).
Enterographa - This mainly tropical genus of c. 53 species includes foliicolous, corticolous, saxicolous, and lichenicolous Roccellaceae with immersed, punctiform to lirelliform, often pseudostromatic ascomata, non-carbonised, hyaline or pale brown exciple and hypothecium, and hyaline, halonate, 3- to many-septate spores. The genus was monographed by Sparrius (2004), with many new species having been described in recent times. Recent phylogenetic studies suggest that the genus is not monophyletic (Ertz & al. 2009, Ertz & Tehler 2011).
Gyrographa - this genus of the Roccellaceae was created to accommodate 2 species formerly included in Opegrapha.
Lecanactis - Due to the unusual high level of homoplasy in morphological and chemical characters, Ertz & Tehler (2011) found that these were of limited use in delimiting taxonomic groups in Arthoniales. Some genera, among them Lecanactis, were found to be paraphyletic, which brought to the description of several new genera. Lecanactis s.str. includes now c. 25 species in tropical to temperate areas and belongs to the Roccellaceae.
Lecanographa - A genus of c. 38 species in tropical, subtropical and temperate regions of both Hemispheres, presently included in the Lecanographaceae. For further details see Egea & Torrente (1993).
Opegrapha - Opegrapha s.str. resently includes c. 300, both lichenised and lichenicolous species.
Pseudoschismatomma – this genus includes the former Opegrapha rufescens-group.
Psoronactis - it includes a single species formerly assigned to Lecanactis.
Roccellographa Ertz & Tehler (2011) presented a new phylogeny of several groups within the Arthoniales based on molecular data, together with important taxonomic implications, among which the inclusion of the crustose species of Peterjamesia D. Hawksw. in the fruticose genus Roccellographa, which now comprises 3 species and is placed in its own family, the Roccellographaceae.
Syncesia - This genus, with 17 accepted species, was monographed by Tehler (1997); six species have been described since then (see e.g. Sundin & Tehler 1998), and now 23 species are known worldwide. The genus, which differs from Chiodecton in the pruinose or tomentose stroma with innate, discoid ascomata, proved to be monophyletic in the phylogeny of Arthoniales by Ertz & Tehler (2011), and belongs to the Roccellaceae.
Zwackhia - this genus was created to accomodate a species formerly treated as an Opegrapha, and is presently included in the Lecanographaceae.
A monograph including most lichenized species of these genera in the Mediterranean region was published by Torrente & Egea (1989).
The present key includes all species, including lichenicolous fungi, known to occur in Italy (Nimis 2016), plus several species which were never reported from Italy, but are known from neighbouring countries, for a total of 61 infrageneric taxa, including Porina multipuncta and Thelopsis corticola, which were previsously considered as belonging to Opegrapha.


Ertz D., Tehler A. 2011. The phylogeny of Arthoniales (Pezizomycotina) inferred from nucLSU and RPB2 sequences. Fungal Divers., 49, 1: 47-71.
Ertz D., Miadlikowska J., Lutzoni F., Dessein S., Raspe O., Vigneron N., Hofstetter V., Diederich P. 2009. Towards a new classification of the Arthoniales (Ascomycota) based on a three-gene phylogeny focussing on the genus Opegrapha. Mycol. Res., 113: 141-152.
Ertz D., Tehler A., Irestedt M., Frisch A., Thor G., van den Boom P.P.G. 2014. A large-scale phylogenetic revision of Roccellaceae (Arthoniales) reveals eight new genera. Fungal Divers., 70, 1: 31-53.
Frisch A., Thor G., Ertz D., Grube M. 2014. The Arthonialean challenge: Restructuring Arthoniaceae. Taxon, 63, 4: 727-744.
Egea J.M., Torrente P. 1993. Cresponea, a new genus of lichenised fungi in the order Arthoniales (Ascomycotina). Mycotaxon, 48: 301-331.
Egea J.M., Torrente P. 1993b. The lichen genus Bactrospora. Lichenologist, 25, 3: 211-255.
Egea J.M., Torrente P. 1994. El género de hongos liquenizados Lecanactis (Ascomycotina). Bibl. Lichenol., 54: 1-206.
Egea J.M., Torrente P., Manrique E. 1993. The Lecanactis grumulosa group (Opegraphaceae) in the Mediterranean region. Plant Syst. Evol., 187: 103-114.
Hillmann G., Schumm F., Thor G. 2016. Excipulum structure of Opegrapha, Alyxoria and Zwackhia. IAL 8, Book of Abstracts, Helsinki: 163.
Nimis P.L. 2016. The lichens of Italy. A second annotated catalogue. EUT, Trieste, 740 pp.
Nimis P.L., Hafellner J., Roux C., Clerc P., Mayrhofer H., Martellos S., Bilovitz P.O. (2018) The lichens of the Alps - an annotated checklist. MycoKeys 31: 1-634.
Sobreira P.N.B., Aptroot A., da Silva Cáceres M.E. 2015. A world key to species of the genus Bactrospora (Roccellaceae) with a new species from Brazil. Lichenologist, 47, 2: 131-136.
Sundin R., Tehler A. 1998. Phylogenetic studies of the genus Arthonia. Lichenologist, 30, 4, 5: 381-413.
Tehler A. 1997. Syncesia (Arthoniales, Euascomycetidae). Fl. Neotrop. Monogr., 75: 1–49.
Torrente P., Egea J.M. 1989. La Familia Opegraphaceae en el Area Mediterranea de la Peninsula Ibérica y Norte de Africa. Bibl. Lichenol, 32: 1- 282.

Last modified: January, 22, 2024