ITALIC 7.0

Polyblastia dominans (Arnold) Zahlbr.

Rabenhorsts. Krypt.-Fl., 2nd ed., 9.1, 1: 421, 1933.. Basionym: Thelidium dominans Arnold - Flora (Regensburg), 52: 263, 1869.

Synonyms:

Distribution: N - TAA (Nascimbene & al. 2022).

Description: Thallus crustose, endosubstratic or rarely very thinly episubstratic, white, yellowish white or pale grey, sometimes with scattered dark lines, smooth to slightly farinose. Perithecia black, 0.2-0.4 mm across (in section), completely immersed in pits of the rock, globose, with a flattened ostiolar region. Involucrellum absent; exciple brown-black, often paler brown in lower part, thicker around the ostiole; hamathecium of periphyses and slender, branched periphysoids; interascal filaments absent; hymenial gel I+ red, K/I+ blue. Asci 8-spored, ellipsoid to clavate, K/I-, fissitunicate, the wall thickened above, with an ocular chamber, dehiscent by extrusion of an endotunica to form a delicate rostrum. Ascospores 3-septate to rarely submuriform with an incomplete longitudinal septum, hyaline, narrowly ellipsoid, 39-54 x 15-18 μm. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: a species resembling P. sepulta (of which it is sometimes considered as a synonym), but with narrowly ellipsoid, larger ascospores; on calcareous rocks; widespread in Europe and most frequent in the Central European mountains; from the Alps there are only a few scattered records; to be looked for further in the Italian Alps. According to Savić & al. (2008), the species belongs to the Thelidium-clade, not to Polyblastia s.str.

Growth form: Crustose endolithic

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Poorly known taxon in need of further study

Commonnes-rarity: (info)

Alpine belt: very rare

Subalpine belt: very rare

Oromediterranean belt: absent

Montane belt: extremely rare

Submediterranean belt: absent

Padanian area: absent

Humid submediterranean belt: absent

Humid mediterranean belt: absent

Dry mediterranean belt: absent

pH of the substrata:

1

2

3

4

5

(info)

Solar irradiation:

1

2

3

4

5

(info)

Aridity:

1

2

3

4

5

(info)

Eutrophication:

1

2

3

4

5

(info)

Poleotolerance:

0

1

2

3

(info)

Altitudinal distribution:

1

2

3

4

5

6

(info)

Predictive model

Index Fungorum GBIF

Source: 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