ITALIC 8.0

Acarospora oligospora (Nyl.) Arnold

Flora, 53: 469, 1870. Basionym: Lecanora oligospora Nyl. - Bot. Not.: 162, 1853.

Synonyms: Acarospora glebosa (Flot.) Körb.

Distribution: N - VG (Castello 2002, Martellos & Castello 2004), Ven, TAA, Lomb, Piem (Isocrono & Ferrarese 2008), Emil (Fariselli & al. 2020). C - Tosc. S - Camp (Aprile & al. 2002), Bas (Nimis & Tretiach 1999).

Description: Thallus crustose, episubstratic, areolate-verrucose, attached by rhizohyphae, forming small, up to 2 cm wide patches. Areoles flat to usually convex, 0.3-1.5 mm wide, 0.3-0.5 mm thick, dispersed or in small groups, olive-brown to dark brown, dull, smooth, epruinose or faintly pruinose, lower surface narrow, subcorticate, pale green from algal layer or pale brown. Cortex paraplectenchymatous, 10-15(-40) µm thick, the upper part brown, the lower part colourless; algal layer continuous, filling most of the areoles; medulla prosoplectenchymatous, white, varying in thickness and usually reduced, continuous with the rhizohyphae. Apothecia one per areole, regularly round, 0.3-1 µm across, with a dark brown to brown-black (reddish when wet) disc and a usually evident thalline margin. Proper exciple thin, forming below the hymenium an up to 20 µm thick, compact, colourless or pale yellowish, prosoplectenchymatous layer with small, rounded to elongated cells; epithecium reddish brown; hymenium colourless, (80-)100-120(-150) µm high, the hymenial gel euamyloid, IKI+ persistently dark blue; paraphyses (1-)1.5-2 µm thick at base, the apical cells barely expanded; subhymenium colourless and 15-20 µm thick; hypothecium indistinct. Asci (16-)24-32(-64)-spored, clavate, the apical dome K/I-, 66-80 x 20-23 µm. Ascospores 1-celled, hyaline, ellipsoid, 9-13(-16) x (5-)6-9 µm. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: a holarctic-temperate species found on basic siliceous rocks (e.g. calciferous sandstone and schist), usually on pebbles, but also on walls, roofing tiles, etc., below the subalpine belt; probably overlooked in Italy, but certainly not common.

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Pioneer species

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: extremely rare

Submediterranean belt: very rare

Padanian area: extremely rare

Humid submediterranean belt: very rare

Humid mediterranean belt: very rare

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

Herbarium samples

Index Fungorum GBIF

Martin Westberg

Sweden

Martin Westberg

Sweden

Martin Westberg

Sweden

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (29919)
2001/12/08

Magnusson A. H. (1935) Acarosporaceae, Thelocarpaceae. - In: Rabenhorst G. L.: Kryptogamen-Flora von Deutschland, Österreich, und der Schweiz-. 2nd- IX. Die Flechten. Abt. 5- 1. Gebr. Borntraeger. Leipzig, pp. 1-318. – Public Domain