Dermatocarpon rivulorum (Arnold) Dalla Torre & Sarnth.

Die Flechten von Tirol: 504, 1902. Basionym: Endocarpon rivulorum Arnold - Verh. zool.-bot. Ges. Wien, 24: 249, 1874.
Synonyms:
Distribution: N - Frl (TSB 4608), TAA (Nascimbene & al. 2007b), Lomb, Piem (Isocrono & al. 2004, Isocrono & Piervittori 2008), VA (Piervittori & Isocrono 1999, Isocrono & al. 2008).
Description: Thallus foliose-umbilicate, monophyllous, rather large, (10-)13-30(-45) mm wide, rather thin (0.24-0.42 mm thick when dry), attached by a central holdfast. Upper surface brown to dark brown, bulging; lower surface more or less concolorous with upper surface, distinctly reticulate. Upper cortex hyaline, except the brown outermost part, with an epinecral layer of compressed hyphae; medulla white; lower cortex colourless except the brown outermost part. Perithecia black, the ostiole immersed or slightly protruding, without involucrellum, the wall colourless except in the brown uppermost part. Hamathecium or periphyses and periphysoids, interascal filaments absent; hymenial jelly hemiamyloid. Asci 8-spored, clavate, the wall thickened above, not amyloid. Ascospores simple to rarely 1(-4)-septate, (14-)16-21(-26) x (5.5-)6- 8(-10.5) µm. Pycnidia rather common, black, sometimes immersed in warts. Conidia bacilliform. Photobiont chlorococcoid. Spot tests: cortex and and medulla K-, C-, KC-, P-, UV-; medulla I-. Chemistry: no lichen substances.
Note: a widespread, cool-temperate to arctic-alpine, circumpolar species found on periodically submerged siliceous rocks, in seepage tracks or along small streams, often completely inundated during summer; it also occurs in melt-water seepages below snow-beds and along lakeshores.
Growth form: Foliose, umbilicate
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Periodically submerged (e.g. in creeks)

Commonnes-rarity: (info)

Alpine belt: very rare
Subalpine belt: rare
Oromediterranean belt: absent
Montane belt: very rare
Submediterranean belt: absent
Padanian area: absent
Humid submediterranean belt: absent
Humid mediterranean belt: absent
Dry mediterranean belt: absent


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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P.L. Nimis CC BY-SA 4.0
TSB 4608


Zahlbruckner A. 1926. Lichenes (Flechten). In: Engler A. (ed.): Die natürlichen Pflanzenfamilien. 2nd ed., vol 8, W. Engelmann, Leipzig, 270 pp.



P.L. Nimis CC BY-SA 4.0
TSB 4608