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 Life habit: lichenized; Thallus: fruticose, erect, prostrate, subpendent or pendent, usually attached by a basal holdfast (rarely unattached), solid or fistulose (R. pollinaria often shows secondarily fistulose branches, true fistulose species not found in the Sonoran area), black ciliate in one species (R. crinita), subdichotomously or irregularly or +palmately branched; branches: solid or fistulose or rarely fenestrate, usually flattened or sometimes terete, linear or +canaliculate, or angular towards the base and at branch apices; surface: yellowish or grayish green or pale yellow, smooth or angular, puberulent in one species (R. puberulenta), occasionally becoming striately ridged; pseudocyphellae: present or almost absent in fistulose species, often conspicuous, ellipsoid, short linear or striate, concave, flat or protruded; often sorediate but lacking isidia; cortex: thin, composed of thick walled hyphae up to 20 µm thick running transversely or irregularly (prosoplectenchymatous), underlain by a supportive chondroid strands of periclinally aligned hyphae either as a uniform sheath or as tissue or ribs composed of agglutinated, thick-walled hyphae; chondroid strands: usually present but almost absent in fistulose species, smooth or cracked forming bundles of hyphae, lacking in some species (R. lacera); medulla: usually laxly arachnoid, sometimes absent when hollow (fistulose species); photobiont: primary one a Trebouxia green alga, secondary one absent; Ascomata: apothecial, substipitate to stipitate, subterminal to terminal, marginal, laminal or lateral; disc: concave or +convex, up to 5(-10 mm) in diam., with or without a white or black margin, often pruinose; margin: usually concolorous with the thallus, with or without pseudocyphellae; asci: elongate-clavate, Bacidia-type, 8-spored; ascospores: hyaline, broadly to narrowly fusiform, or broadly ellipsoid, 1(-3)-septate; Conidiomata: pycnidial but usually absent, usually pale colored or rarely black, laminal; conidia: bacilliform, hyaline, c. 3.5 x 0.5 µm; ; Secondary metabolites: cortex with usnic acid and atranorin (±trace); medulla often with orcinol or ß-orcinol depsides or depsidones, triterpenes and aliphatic acids; Geography: world-wide, from coastal to alpine habitats; Substrate: on bark, wood, soil (very rare) and rock.; Notes: Rundel and Bowler (1974) established a new genus Trichoramalina, based on Ramalina crinita Tuck. In the protologue they stressed the presence of black pycnidia, terminal cilia and thicker cortex of branches in the new genus. However, R. crinita has characteristic features of Ramalina such as 2-celled ascospores, pale or secondarily black pigmented pycnidia, bacilliform conidia, short linear pseudocyphellae and a prosoplectenchymatous cortex. Although the presence of black cilia is unique for this species (and one in Africa), thicker cortices and black pigmented pycnidia are also observed in other species of Ramalina, especially R. siliquosa group. Therefore Trichoramalina is treated as a synonym of Ramalina in this treatment. Ramalina can be separated from Niebla, another genus of the family Ramalinaceae in the Sonoran region, by the presence of pseudocyphellae, its prosoplectenchymatous cortex and its pale pycnidia. In addition species of Ramalina never produce (-)-16 α-hydroxykaurane that is often found in Niebla. North American members of Niebla have black pycnidia and those with rigid blades and thick cortices have an anticlinal palisade layer of cells in the cortex, though some forms have a simpler cortex. A major challenge with Ramalina from the Sonoran region is dealing with the European species reported by R.H. Howe (1914). He did not cite specimens, making it impossible to determine precisely his concepts of the different species. However, we have found some Howe identified material in FH and US and make the following conclusions: (1) No authentic material of Ramalina calicaris, a predominately European species, has been found for the Sonoran region, and some material identified as such by Howe proved to be R. leptocarpa; (2) Ramalina calicaris var. farinacea as determined by Howe is R. farinacea; (3) Ramalina fastigiata is reported and most reports for North America now are called R. americana, but in the Southwest the name was most likely applied incorrectly to R. sinensis.[Rick Reifner reported this species based on an identification by John Thompson.]; (4) Ramalina fraxinea is another European species reported by Howe, but we suspect that it may have been an identification based on what is now regarded as Ramalina sonorensis; (5) Ramalina linearis, as identified by Howe, is R. leptocarpa. Potentially 

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© Lichen Unlimited: Arizona State University, Tempe.

Source: Lichen Flora of the Greater Sonoran Desert Region

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