ITALIC 8.0

Verrucaria nodosa Orange

Lichenologist, 45: 312, 2013.

Synonyms:

Distribution:

Description: Thallus crustose, episubstratic, dark brown in exposed sites to greenish brown in shade, 70-500 μm thick, not subgelatinous when wet, consisting of crowded and overlapping, 30-325 μm thick goniocyst-like units with brown-pigmented walls, forming an uneven crust with sparse secondary cracks. Perithecia black, forming low to moderately conical-hemispherical, 0.22-0.45 mm wide projections which are naked or with an irregular thalline cover in lower part. Involucrellum appressed to exciple in upper part, diverging in lower part, steeply conical-hemispherical in outline, often reaching to base-level, densely pigmented throughout, or with a pale area near the base, the pigment dark brown to dark reddish brown, the ostiolar area often with a dark green pigment; exciple 190-310 μm across, colourless or the outer layer pigmented throughout; hamathecium of 25-40 μm long periphysoids, interascal filaments absent; hymenial gel hemiamyloid, I+ red (I+ blue at very low concentrations of I), K/I+ blue. Asci 8-spored, clavate, I-, fissitunicate, the wall thickened above, with an ocular chamber, dehiscent by extrusion of an endotunica to form a delicate rostrum, Verrucaria-type. Ascospores 1-celled, hyaline, ellipsoid (17-) 20.5-24(-28) x (8-) 9-10.5(-11.5) μm, (2-)2.1-2.5(-3) times as long as wide. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances

Note: a species described from the British Isles and also known from southern Corsica (Roux & Coll. 2025), growing on siliceous rocks beside streams, more rarely on surfaces with frequent water seepage after rain. To be looked for in Italy.

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Periodically submerged (e.g. in creeks)

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