ITALIC 7.0

Acarospora rehmii H. Magn.

K. svenska Vetensk-Akad. Handl., ny föl. 7, 4: 185, 1929

Synonyms: Acarospora tongletii f. rehmii (H. Magn.) Clauzade & Cl. Roux

Distribution: N - VG (Magnusson 1936)..

Description: Thallus crustose, episubstratic, areolate-subsquamulose, densely white-pruinose, the areoles 0.5-1(-2) mm wide, 0.3-0.6 mm thick, at first flat, then convex and fissured or reticulately grooved, dispersed or usually contiguous and separated by deep fissures, reddish brown, but almost always appearing white due to a thick layer of pruina, the margin most often dark. Epicortex to 30 µm thick, with small crystals dissolving in K; cortex 20-70 µm thick, brown in upper part, colourless in lower part, the cells mostly 3-4 µm wide; algal layer continuous; medulla white, to 0.4 µm thick, I-. Apothecia lecanorine, immersed, 0.3-1 mm across, with a black to brown-black sometimes slightly pruinose disc and a thick, often radially fissured thalline margin. Proper exciple prosoplectenchymatous, I-; epithecium brown; hymenium (80-)120-150 µm high, I+ blue rapidly turning red-brown, K/I+ blue; paraphyses 1-3 µm thick, the apical cells hardly swollen; hypothecium thin, colourless. Asci 100-200-spored, clavate, the apical dome K/I-. Ascospores 1-celled, hyaline, ellipsoid, 6-9(-12) x 2.5-3.5(-4) µm. Pycnidia immersed. Conidia simple, ellipsoid, c. 2 x 1.5 µm. Photobiont chlorococcoid. Spot tests: cortex and medulla K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: This is a distinct species according to Knudsen & Kocourková (2020), differing from A. paupera in the absence of norstictic acid. It grows on calciferous sandstone below the montane belt, and it might be more widespread in Italy.

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: absent

Submediterranean belt: very rare

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

Elena Pittao CC BY-SA 4.0; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (2272)

Elena Pittao CC BY-SA 4.0; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (2272)