ITALIC 8.0

Physconia subpulverulenta (Szatala) Poelt var. atlantica Poelt

Nova Hedwigia, 12: 127, 1966.

Synonyms:

Distribution: C - Sar (Zedda 1995, 2002, Zedda & Sipman 2001).

Description: Thallus foliose, heteromerous, dorsiventral, narrow-lobed, rather tightly adpressed, forming up to 6 cm wide rosettes. Lobes elongate, 0.5-1(-1.3) mm wide, rather thin, flat to concave, of variable colour, from brown in weakly pruinose forms to white in strongly pruinose ones, with some white pruina at least at tips, with numerous, cylindrical to slightly flattened, mostly marginal isidia-like outgrowths. Lower surface mostly black (whitish in marginal parts), with dense, dark, squarrose rhizines. Upper and lower cortex prosoplectenchymatous, the hyphae mostly running perpendicularly to the surface; medulla yellowish. Apothecia lecanorine, sessile, to 3 mm across, with a usually white-pruinose disc and a persistent, often lobulate thalline margin, the lobules usually isidiate. 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, ellipsoid, 24-30 x 12-18 μm, thickened at septum but not at apices, Physconia-type. Photobiont chlorococcoid. Spot tests: upper cortex K-, C-, KC-, P-; medulla K+ yellow, C+ yellow, KC+ yellow-orange, P-. Chemistry: medulla with variolaric acid.

Note: a critical taxon, which needs further study. It was included in the Italian red list of epiphytic lichens as “Data Deficient” (Nascimbene & al. 2013c).

Growth form: Foliose, narrow lobed

Substrata: bark

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)

Poorly known taxon in need of further study

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: extremely 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

P.L. Nimis CC BY-SA 04

TSB 8136

Pier Luigi Nimis; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (8136)