ITALIC 8.0

Arthonia donoraticensis Brackel

Borziana, 6: 13, 2015.

Synonyms:

Distribution: C - Tosc (Brackel 2025).

Description: Thallus inapparent, not lichenized, developing inside the thalli of Flavoparmelia-species, causing no apparent damage. Apothecia arthonioid, 0.1-0.8 mm across, breaking through the host cortex, then superficial, scattered or in loose groups, round and convex, pillow-like, emarginate, dark brown to black when moist, rough and glossy, sometimes covered with remnants of the host cortex. Proper exciple lacking; epithecium thin, patchily medium to dark brown, K-; hymenium subhyaline to very pale brown, c. 40 μm high, K-, I+ wine red, K/I+ persistently blue; paraphysoids septate, branched and anastomosing, 1-2 μm thick, apically perpendicular bent over the asci for up to 8 μm (and more), this part up to 2.5 μm thick and pale brownish grey to almost black in the most exposed parts; hypothecium pale brown, c. 20 μm high, K-. Asci 3-8-spored, fissitunicate, globose to saccate, with a tiny but distinct K/I+ blue ring in the ocular chamber and a thin K/I+ blue layer around the ascus wall, the endoplasm I+ deep orange, 20-28 x 15-20 μm. Ascospores 1-septate, hyaline, narrowly ellipsoid to soleiform or somehow irregular, with a broader upper cell, 7-10 x 3-4.2(-5) μm. Photobiont absent. Spot tests: K-, C-, KC-, P-. Chemistry: without lichen substances.

Note: a recently-described lichenicolous fungus growing on the thalli of Flavoparmelia-species, hitherto known from Italy and northwestern France, but probably more widespread. For further details see Brackel (2025).

Growth form: Lichenicolous fungus

Substrata: bark

Reproductive strategy: mainly sexual

paras Flavoparmelia caperata and Flavoparmelia soredians

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: absent

Submediterranean belt: absent

Padanian area: absent

Humid submediterranean belt: absent

Humid mediterranean belt: extremely rare

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

Wolfgang von Brackel - Source: Brackel von W. 2025. Lichenicolous fungi from the northern Apennines and foreland (Italy). Borziana, 6: 5-53.

taly, Toscana, Provincia di Livorno, N San Vincenzo, SSW Donoratico, dune scrub, on Juniperus macrocarpus, on Flavoparmelia soredians, 10 m, 43°06’52,9’’N, 10°32’23,5’’E, 29.8.2015, leg. W. & G. v. Brackel
Arthonia donoraticensis, holotype: habitus on Flavoparmelia soredians. The net of brown belongs to an undescribed Talpapellis species. Bar = 250 μm.

Wolfgang von Brackel - Source: Brackel von W. 2025. Lichenicolous fungi from the northern Apennines and foreland (Italy). Borziana, 6: 5-53.

Arthonia donoraticensis, asci, paraphysoids, ascospores. Bar = 10 μm.