Life habit: lichenized; rarely lichenicolous Thallus: crustose, squamulose, rarely bullate, effuse, scattered granules, warted or areolate, rarely endolithic or absent, papillate or somewhat lobed, with appressed or raised areoles prothallus: sometimes present, grayish to dark brown upper surface: grayish white to brown-black, smooth to warty- papillate, dull to shiny, rarely pruinose, rarely blastidiate upper cortex: usually developed, containing paraplectenchymatous, sometimes anticlinal hyphae, covered by an upper epinecral layer, sometimes containing granular crystals photobiont: primary one a chlorococcoid green alga, secondary one absent; algal cells: 5-18 µm in diam. medulla: sometimes containing weakly conglutinate hyphae throughout, often absent or indiscernible lower cortex: absent in crustose species, rudimentary in squamulose species lower surface: present in a few squamulose species, without specialized attachment organs Ascomata: apothecial, sessile, erumpent, appressed to strongly constricted at base, marginate, sometimes becoming immarginate, 0.2-2 mm in diam. disc: pale brown , ±orange to black-brown, rarely piebald, at first mostly flat, often becoming convex, sometimes weakly concave, sometimes weakly or densely pruinose margin: usually thalline, varying from thin and entire to crenate or strongly flexuous amphithecium: present in most species, often composed of ±thick-walled conglutinate hyphae with angular to rounded lumina, with a colorless inner part and a pale to dark reddish brown outer rim; medulla: sometimes containing granular crystals or rarely clusters of more bigger crystals parathecium: developed in several species, sometimes paraplectenchymatous, the cells at outer edge rounded to elongated, often conglutinate epihymenium: hyaline to pale to dark reddish brown, often K+ bright pink to deep purplish brown, sometimes containing crystals of calcium oxalate hymenium: hyaline, I+ blue, 30-100 µm; paraphyses: straight, asci: ±: clavate, Bacidia-type, 8(-16)spored ascospores: hyaline, (0-)1-3(-5) septate, broadly ellipsoid, elongate-ellipsoid to rarely fusiform, thin-walled Conidiomata: pycnidial, found in all species treated in this study, globose to somewhat pyriform, laminal, hyaline below, pale brown, dark brown to blackish brown above, 50-200 µm in diam.; ostiole: black, often rugose in appearance, immersed to slightly raised; conidigenous cells: cylindrical, filamentous, branched, up to 15 µm long and 2 µm in diam. conidia: filiform, slightly to strongly curved, 10-25 x c. 0.8 µm Secondary metabolites: only unknown terpenes have been found in some Sonoran species, atranorin was formerly known in only one Sonoran Lecania species, L. cyathiformis, but that species has been transferred to another genus (Solenopsora) Geography: predominantly in temperate and mediterranean areas although extending to arid and arctic/alpine environments, often maritime or coastal Substrate: on soil, acidic or calcareous rocks, stones, artificial substrates such as old walls and gravestones, bark and sometimes on wood, rarely on mosses over bark or rocks. Notes: Many epiphytic 'Lecania' specimens are misidentifications of Cliostomum griffithii (Sm.) Coppins. Artificial substrates, on which L. erysibe and L. rabenhorstii often have been found in Europe, such as those in churchyards have also been investigated recently here. In contrast to such habitats in Europe, only L. rabenhorstii has rarely been found. The only Sonoran species from such habitats is L. pacifica. Herbarium specimens identified as L. erysibe were incorrectly identified, and that species has not yet been confirmed for the Sonoran area. Several Lecania species are hosts for lichenicolous fungi, e.g. Toninia talparum Timdal, T. subtalparum van den Boom (on L. brunonis, L. dudleyi, L. fructigena, and L. pacifica), and rarely an Arthonia sp. and a Stigmidium sp. Relationships of some genera with Lecania and their delimitation and nomenclature may soon be modified, as ITS sequence data become more and more available. Based on the ascus-type, the genera Bacidia and Bacidina are probably most closely related to Lecania. Furthermore, the occurrence of hyaline, 1-septate ascospores also occur in other genera, such as Solenopsora, Catillaria, Halecania and Placodiella. The latter genus is insufficiently known and is in urgent need of revision. Even the genus Solenopsora contains poorly-known species. It apparently belongs to Catillariaceae based on its ascus-type (Catillaria-type), its paraphyses with a dark brown cap that are not or weakly conglutinated and its short bacilliform conidia. Lecanora is distinguished from Lecania by its different ascus-type, simple ascospores and non-conglutinated paraphyses.