Hydropunctaria rheitrophila (Zschacke) C. Keller, Gueidan & Thüs

Taxon, 58: 194, 2009. Basionym: Verrucaria rheitrophila Zschacke - Hedwigia, 67: 67, 1922.
Synonyms: Verrucaria cinereolutescens Zschacke; Verrucaria kernstockii Zschacke; Verrucaria minutipuncta Erichsen; Verrucaria sagedioides Servít; Verrucula rheitrophila (Zschacke) M. Choisy
Distribution: N - Ven (S-L12313), TAA (Nascimbene & al. 2007b). C - Sar (Herb. Nascimbene 2644).
Description: Thallus crustose, episubstratic, 60-95 μm thick, subgelatinous when wet, smooth or roughened, usually continuous but sometimes with sparse cracks, pale brownish green to olive green or dark green, with sparse to numerous black dots, delimited by a whitish prothallus or, from conspecific thalli, by black lines. Cortex paraplectenchymatous, poorly differentiated, c. 20 μm thick, the cell walls yellowish brown to blackish brown; photobiont cells arranged in vertical rows; medulla paraplectenchymatous, with black dots or columns; black basal layer absent or sometimes only partially present. Perithecia completely immersed in the thallus only slightly projecting, covered with a thalline layer, usually visible as black dots. Involucrellum from apical and poorly developed to well-developed in the upper half of the exciple, often spreading outwards and downwards; exciple (90-)110-210 μm across, colourless or partly brown; hamathecium of periphyses and periphysoids, interascal filaments absent, the periphyses 20-30 x 1.5-3 μm. 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, (7.5-)10-12(-16) x (4.7-)6-7(-9) μm, without a perispore. Photobiont chlorococcoid. Spot tests: thallus and medulla K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: on both siliceous and calcareous rocks in cold, fast-running streams, in permanently submerged to frequently wetted places; widespread in the Holarctic region and also known from the Southern Hemisphere, the species is widely distributed in the Alps, but not common.
Growth form: Crustose
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Periodically submerged (e.g. in creeks)

Commonnes-rarity: (info)

Alpine belt: extremely rare
Subalpine belt: very 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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Predictive model
Herbarium samples

Source: http://fungi.myspecies.info/all-fungi/hydropunctaria-rheitrophila - CC BY-NC


Zschacke, H. (1934) Epigloeaceae, Verrucariaceae und Dermatocarpaceae. In: Dr. L. Rabenhorst‘s Kryptogamen-Flora, Band 9, Abt. 1, Teil 1. Akademische Verlagsgesellschaft, Leipzig, 695 pp. - Public Domain


Zschacke, H. (1934) Epigloeaceae, Verrucariaceae und Dermatocarpaceae. In: Dr. L. Rabenhorst‘s Kryptogamen-Flora, Band 9, Abt. 1, Teil 1. Akademische Verlagsgesellschaft, Leipzig, 695 pp. - Public Domain