ITALIC 8.0

Verrucaria acrotella Ach.

Meth. Lich.: 123, 1803.

Synonyms: Verrucaria aethiobola var. acrotella (Ach.) H. Olivier

Distribution: N - TAA (Nascimbene & al. 2022), Lig. C - Tosc, Sar. S - Si.

Description: Thallus crustose, thinly episubstratic, dark brown to black, up to 0.2 mm thick, usually continuous, granular to irregularly and weakly rimose, poorly delimited, sometimes with a thin, brown, fimbriate prothallus. Cortex and medulla poorly developed, the algal cells dispersed throughout the thallus thickness. Perithecia black, 0.1-0.15(-0.23) mm across, immersed in the thallus, with at least the upper third projecting. Involucrellum black, adpressed to exciple and slightly incurved beneath, not covered with a thalline layer, broadening to 40-60 µm at base; exciple 0.2-0.3 mm across, often apple-shaped, the wall reddish brown, c. 10 µm thick; hamathecium of periphyses and periphysoids measuring c. 20 x 2.5-4 µm, interascal filaments absent; hymenial gel hemiamyloid, I+ red (I+ blue at very low concentrations of I), K/I+ blue. 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 to narrowly ellipsoid, 12-21 x (5-)7-9(-10) µm. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: a very poorly known species found on siliceous rocks, mostly on small pebbles; see also comment in Nimis (1993: 731), and Orange (2008).

Growth form: Crustose

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: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: very rare

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

Source: Servit, M 1949: Nove nebo mene zname druhy lisejnikove celedi Verrucariaceae. Species Verrucariacearum (Lichenes) novae vel minus cognitae. - Sbornik Narodniho Musea v Praze 5(9): 1-51. Tab.1 - 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