ITALIC 8.0

Rhizocarpon rapax V. Wirth & Poelt

Mitt. bot. Staatss. München, 8: 196, 1970.

Synonyms:

Distribution: N - TAA, Piem (TSB s.n.).

Description: Thallus crustose, areolate, pale to bright yellow-green, forming 5-8 mm wide, sometimes confluent patches on the thalli of other crustose lichens, usually delimited by a thin, dark prothallus. Areoles developing from those of the host, angular to more or less round, 0.2-0.5(- 0.8) mm wide, flat to slightly convex. Cortex indistinctly differentiated, 25-40 µm thick; medulla largely filled with algae, the lower part white, I+ blue. Apothecia lecideine, black, immersed, usually angular, 0.5-0.8 mm across, not surrounded by crescent-shaped areoles, with a usually flat disc and a thin, often persistent proper margin. Proper exciple thin, dark to red-brown; epithecium red-brown, K+ reddish violet; hymenium colourless, c. 135 µm high; hypothecium brown-black. Asci (6-)8-spored, clavate, fissitunicate, with a well-developed tholus, lacking an ocular chamber, Rhizocarpon-type. Ascospores mostly submuriform, mostly with a longitudinal and a transverse septum arranged crosswise, 2-6 celled in optical view, grey-brown to brown-black, very variable in outline (globose, ellipsoid to almost cubical), 14-23 x 10-16 µm, halonate. Photobiont chlorococcoid. Spot tests: medulla K-, C-, KC-, P+ yellow. Chemistry: cortex with rhizocarpic acid; medulla with psoromic acid.

Note: on siliceous rocks near and above treeline, starting the life-cycle on the thalli of different crustose lichens; related to Rh. tinei, but differing in the parasitic growth; probably overlooked, and more frequent in the Alps, especially in rainy areas.

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

paras Acarospora

Commonnes-rarity: (info)

Alpine belt: rare

Subalpine belt: extremely rare

Oromediterranean belt: absent

Montane belt: absent

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