ITALIC 8.0

Arthonia clemens (Tul.) Th. Fr.

K. Svenska Vetensk.-Akad. Handl., n. ser. 7, 2: 46, 1867. Basionym: Phacopsis clemens Tul. - Ann. Sc. Nat. Bot., ser. 3, 17: 124, 1852.

Synonyms: Arthonia vagans var. lecanorina Almq.; Coniangium clemens (Tul.) Stein; Conida clemens (Tul.) A. Massal.

Distribution: N - Ven, TAA (Hafellner 1995b, Nascimbene & al. 2004), Lomb (Fleischhacker & al. 2016 ), Piem (Isocrono & al. 2004).

Description: Thallus inapparent, not lichenized, the hyphae developing inside the apothecial discs of Rhizoplaca species. Apothecia arthonioid, immersed in those of the host, more or less round, to 2 mm across, with a black, often marginally paler, slightly convex disc, without a distinct proper margin. Exciple poorly developed, not evident; epithecium olive-brown, 15-20 µm high; hymenium colourless, 25-35 µm high, I+ red, K/I+ blue; paraphysoids branched, the apical cells enlarged, to 3 µm wide; hypothecium colourless, c. 20 µm high. Asci 8-spored, broadly clavate to subglobose, distinctly stipitate, semi-fissitunicate, with a large, non-amyloid apical dome, and a distinct ocular chamber, Arthonia-type, 28-33 x 14-17 µm. Ascospores 1-septate, hyaline, obovate, one cell larger and longer, 10-14 x 4-7 µm, without an epispore. Photobiont absent. Spot tests: K-, C-, KC-, P-. Chemistry: without lichen substances.

Note: a holarctic lichenicolous fungus growing in the apothecia of Rhizoplaca chrysoleuca, very much confused with other species in Italy (see note on A. galactinaria). Records from hosts othar than Rhizoplaca are not reported here.

Growth form: Lichenicolous fungus

Substrata: rocks

Reproductive strategy: mainly sexual

paras Rhizoplaca

Commonnes-rarity: (info)

Alpine belt: very rare

Subalpine belt: very rare

Oromediterranean belt: absent

Montane belt: extremely rare

Submediterranean belt: extremely rare

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

Serge Poumarat - Source: https://www.afl-lichenologie.fr/Photos_AFL/Photos_AFL_A/Textes_A2/Arthonia_clemens.htm

France, session AFL Pyrénées-Orientales - 2012