ITALIC 8.0

Rhizocarpon subpostumum (Nyl.) Arnold

Verh. zool.-bot. Ges. Wien, 27: 554, 1877. Basionym: Lecidea subpostuma Nyl. in Arnold - Verh. zool.-bot. Ges. Wien, 27: 554, 1877.

Synonyms:

Distribution: N - TAA (Nascimbene & al. 2022), Piem (Jatta 1909-1911).

Description: Thallus crustose, episubstratic, grey-brown, areolate, forming patches to 4 cm in diam., rarely delimited by a thin black prothallus. Areoles 0.3-0.6 mm wide, flat to slightly convex, polygonal to rounded, epruinose. Medulla white, I-. Apothecia lecideine, black, 0.3-0.5(-0.6) mm across, with a flat, epruinose disc and a distinct, often finally excluded proper margin. Proper exciple dark brown in outer part, K+ purple; epithecium brown, brown-black or greenish brown, K+ purple; hymenium colourless, (60–)78–150 µm high; paraphysoids strongly conglutinated, richly branched and anastomosing, the apical cells clavate; hypothecium brown. Asci 8-spored, clavate, fissitunicate, with a well-developed tholus, lacking an ocular chamber, Rhizocarpon-type. Ascospores 3-septate to usually weakly submuriform, with (4-)5-7(-8) cells in optical view and 1-2 oblique septa, at first hyaline, sometimes turning pale brown when overmature, narrowly ellipsoid to ellipsoid, (15-)18-23(-25) x (7-)9-13 µm, halonate. Photobiont chlorococcoid. Spot tests: cortex K-, C-, KC-, P-; medulla P- or P+ yellow, sometimes fleeting C+ and KC+ pink. Chemistry: medulla with stictic acid, sometimes with additional gyrophoric acid.

Note: a poorly known silicicolous species, differing from Rh. postumum in the K+ red epithecium.

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: very rare

Subalpine belt: very 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

Index Fungorum GBIF

Einar Timdal - Source: http://nhm2.uio.no/lav/web/index.html - CC BY-NC