ITALIC 8.0

Thelidium impressulum Zschacke

Hedwigia, 62: 125, 1920.

Synonyms:

Distribution:

Description: Thallus crustose, endosubstratic, forming small, orbicular, whitish grey patches on the thalli of endolithic Verrucaria-species. Perithecia black, 0.2(-0.3) mm across (in section), usually crowded, half-immersed, with a hemispherical, apically flattened upper part. Involucrellum reaching down to the base of the perithecium; exciple thin, brown-black throughout; hamathecium of periphyses and periphysoids, interascal filaments absent; hymenial gel I+ red (I+ blue at very low concentrations of I), K/I+ blue. Asci 8-spored, ellipsoid to clavate, I-, fissitunicate, the wall thickened above, with an ocular chamber, dehiscent by extrusion of a delicate rostrum. Ascospores 1-septate, hyaline, ellipsoid, 12-16 x 7-10 pm, surrounded by a gelatinous perispore. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: on calcareous rocks (dolomite at type locality), on the thalli of endolithic Verrucaria-species above the submediterranean belt; not rare in the Alps but probably regionally still undercollected; to be looked for in the Italian Alps.

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

paras endolithic Verrucaria-species

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

Source: Keissler K. von 1938. Pyrenulaceae, Mycoporaceae, Coniocarpineae. In: Rabenhorst G L: Kryptogamen-Flora von Deutschland, Österreich und der Schweiz. 2nd, IX, Die Flechten, Abt. 1, 2. Gebr. Borntraeger, Leipzig, pp. 1-846.