ITALIC 8.0

Physcia magnussonii Frey

Erg. wiss. Unters. Schweiz. Nationalpark Unterengadin, n. F. 3, 27: 480, 1952.

Synonyms: Physcia aipolia var. subincisa (Th. Fr.) Lynge; Physcia stellaris var. subincisa Th. Fr.

Distribution: N - TAA, Lomb (Favero-Longo & al. 2023), Piem (TSB 34161), VA (Piervittori & Isocrono 1997, 1999, Piervittori & al. 2001, Isocrono & al. 2008), Emil (Fariselli & al. 2020). C - Tosc (Giordani & al. 2009).

Description: Thallus foliose, heteromerous, dorsiventral, narrow-lobed, closely adpressed, forming orbicular, up to 8 cm wide rosettes. Lobes to 3 mm wide, usually overlapping, more or less convex, whitish grey to brownish grey, emaculate, distinctly and densely white-pruinose, the margins often down-turned at lobe-tips. Lower surface white to brownish, with a few, stout, simple rhizines. Upper cortex paraplectenchymatous; medulla white. Apothecia common, lecanorine, to 3 mm across, with a usually white-pruinose, otherwise black disc and a smooth thalline margin. Epithecium brown; hymenium and hypothecium colourless; paraphyses slender, simple or forked in upper part, the apical cells clavate, with a thin, dark brown cap. Asci 8-spored, clavate, the K/I+ blue tholus penetrated by a faintly amyloid apical cushion with parallel or diverging flanks, the wall K/I-, surrounded by a K/I+ blue outer layer, Lecanora-type. Ascospores 1-septate, brown, narrowly ellipsoid, 16-24 x 6-9 µm, the wall with a distinct verrucose ornamentation, thickened at apex and at septum, Physcia-type, the wall ornamented. Pycnidia common, immersed, black. Conidia subcylindrical. Photobiont chlorococcoid. Spot tests: upper cortex K+ yellow, C-, KC-, P- or P+ faintly yellow; medulla K- or K+ pale pink, C-, KC-, P-. Chemistry: upper cortex with atranorin; medulla with accessory zeorin and/or variolaric acid.

Note: on steeply inclined surfaces of base-rich siliceous rocks, often starting its development in fissures of the rock; for Italy hitherto known only from the Alps and the northern Apennines, but is likely to be found on some Mediterranean mountains with suitable substrata.

Growth form: Foliose, narrow lobed

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

On otherwise dry surfaces with short periods of water seepage after rain

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: rare

Oromediterranean belt: absent

Montane belt: very 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

Herbarium samples

Index Fungorum GBIF

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

Herbarium: TSB (20316)
2001/12/11