ITALIC 8.0

Usnea subcornuta Stirt.

Scott. Natural., 6, 3: 107, 1881

Synonyms:

Distribution:

Description: Thallus fruticose-filamentous, greenish, shrubby, branching isotomic- or anisotomic dichotomously with divergent branches, up to 3 cm long. Main branches cylindrical, without foveolae and transverse cracks, pale orange-red or greenish at base. Lateral branches (at least the largest ones) constricted at attachment point. Papillae sparse, verrucose, most frequent on main branches; tubercles absent; fibrils scattered throughout the branches, up to 3 mm long. Soralia irregular in outline, plane to slightly stipitate, developing from cortex, occupying less than half the diameter of the branch, but usually confluent into irregular, larger patches; isidiomorphs rare, 0.1-0.15 mm long. Cortex shiny in longitudinal section, thin (6-9% of total branch thickness); medulla heterogeneous, with a narrow, compact, pink, red or orange layer below the cortex, otherwise loose, thick (20-29 %); central axis white, thin (30-35%); ratio axis/medulla >1. Apothecia not observed. Photobiont chlorococcoid. Spot tests: cortex K-, C-, P-; medulla K+ yellow slowly turning orange-red, C-, KC-, P+ deep orange. Chemistry: cortex with usnic acid; medulla with norstictic and stictic acids (major), and substances of the stictic acid complex (accessory), plus an unidentified fatty acid.

Note: a very rare corticolous species, known only from a few localities in Europe, with a mainly western, Mediterranean-Macaronesian distribution and disjunct stations in the western Caucasus. To be looked for in Tyrrhenian Italy.

Growth form: Fruticose filamentous

Substrata: bark

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)

Restricted to humid-warm, oceanic areas

pH of the substrata:

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Solar irradiation:

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Aridity:

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Eutrophication:

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Poleotolerance:

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Altitudinal distribution:

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Predictive model

Index Fungorum GBIF

Tiiu Tõrra; Owner: Tiiu Tõrra - Institute of Ecology and Earth Sciences, University of Tartu, Estonia

Tiiu Tõrra; Owner: Tiiu Tõrra - Institute of Ecology and Earth Sciences, University of Tartu, Estonia

Tiiu Tõrra; Owner: Tiiu Tõrra - Institute of Ecology and Earth Sciences, University of Tartu, Estonia

Tiiu Tõrra; Owner: Tiiu Tõrra - Institute of Ecology and Earth Sciences, University of Tartu, Estonia

Tiiu Tõrra; Owner: Tiiu Tõrra - Institute of Ecology and Earth Sciences, University of Tartu, Estonia

Tiiu Tõrra; Owner: Tiiu Tõrra - Institute of Ecology and Earth Sciences, University of Tartu, Estonia

Robert Lücking ; Owner: Robert Lücking