ITALIC 8.0

Opegrapha geographicicola (Arnold) Hafellner

Herzogia, 10: 12, 1994. Basionym: Phaeospora geographicicola Arnold - Verh. K.-K. zool.-bot. Ges. Wien, 46: 140, 1896.

Synonyms: Leptosphaeria geographicicola (Arnold) Sacc. & D. Sacc.

Distribution:

Description: Thallus inapparent, not lichenized, the hyphae growing inside the thalli of yellow, more rarely brown Rhizocarpon-species. Apothecia rounded to short elliptical, immersed singly or in small groups of 2-3 in the host areoles, dark brown to black, 0.25-0.35 mm across, the rim low and c. 0.03-0.04 mm wide. Proper exciple dark olive-brown, extending below the hnymenium, 60-70 μm wide laterally, up to 40-60 μm thick below the hymenium; epithecium pale brownish olive, c. 30-35 μm high; hymenium colourless to pale olive-brown, 80-100 μm high, hemiamyloid, I+ blue turning red, K/I+ blue; paraphyses 2.5-3.5 μm thick at mid-level, with c. 0.5 μm thick walls, the apical cells to 3-5 μm wide and occasionally with a dark brown cap; subhymenium colourless, 35-40 μm high. Asci (6-)8-spored, broadly clavate, 60-80 x 17-22 μm, with a tiny K/I+ blue ring. Ascospores (2-)3-septate, medium to dark brown, narrowly ellipsoid with rounded to subacute ends, constricted at septa, (21-)22.5-26(-27) x 7.5-9 μm, with a strong ornamentation of dark brown warts, the young ones with an up to 2 μm thick, hyaline perispore, the septa I+ blue. Photobiont absent. Spot tests: all negative. Chemistry: unknown, but probably without lichen substances.

Note: a holarctic and bipolar lichenicolous fungus growing on the thalli of Rhizocarpon-species, known from Alaska, Austria, Greenland, New Zealand, Poland, Scandinavia and Spain. The description is based on that by Frisch & al. (2022). To be looked for in the Italian Alps.

Growth form: Lichenicolous fungus

Substrata: rocks

Reproductive strategy: mainly sexual

paras yellow Rhizocarpon-species

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

Source: Frisch, A., Holien, H., Klepsland, J.T., Suija, A. & Bendiksby, M. 2022. New data on lichenicolous fungi in Norway. Graphis Scripta 34 (7): 59–133. Oslo. ISSN 2002-4495. - CC BY-4.0

Opegrapha geographicola (on Rhizocarpon geographicum). TRH-L-24906. A. Habitus, B. Ascus with semi-mature ascospores. Scale: A = 2 mm, B = 20 μm. Photos: A. Frisch. A. Frisch.