ITALIC 8.0

Arthonia destruens Rehm

in Rabenhorst, Lich. Eur. Exs.: nr. 816, 1868.

Synonyms:

Distribution: C - Marc (Brackel 2015, 2016), Abr (Brackel 2015, 2016). S - Si (Brackel 2008b, 2016).

Description: Thallus inapparent, not lichenized, developing on the thalli of species of Physcia. Apothecia arthonioid, scattered to clustered in cushion-like groups of c. 10, often confluent, rounded to slightly irregular in outline, 0.l-0.25(-0.4) mm across, erumpent from the host thallus and becoming sessile, black, with a rough surface, in section 50-100 μm tall. Thalloconidia rarely formed at the periphery of the apothecia, roundish, aseptate, c. 3.5-5 um across. Proper exciple poorly developed, formed by a down-turning of the epithecium; epithecium yellowish brown, 5-15 μm high, covered with a c. 5 μm high, hyaline gelatinous coat, I+ blue; hymenium yellowish brown, 25-50 μm high, I+ and K/I+ blue, K+ purplish violet (yellowish parts); paraphysoids scanty, occasionally branched and anastomosing; hypothecium dark brown with a yellowish hue, 20-45 μm high, I+ reddish brown, K/I+ blue, K+ purplish violet. Asci 4-8-spored, broadly clavate, semi-fissitunicate, with a large apical dome and a distinct ocular chamber, Arthonia-type, lacking any I+ or K/I+ structures, 29-43 x 11-15 μm. Ascospores (1-)2-septate, slightly constricted at septum, with a slightly larger upper cell, hyaline to brown when overmature, oblong-ovoid, 10-17 x 5-7 μm, the wall of mature spores finely verrucose. Photobiont absent. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: a lichenicolous fungus whose known hosts, in the narrower concept of Grube & al. (1995), are Physcia aipolia and P. stellaris; a rare species, perhaps more widespread in Italy than the few records would suggest.

Growth form: Lichenicolous fungus

Substrata: bark

Reproductive strategy: mainly sexual

paras Physcia spp.

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: rare

Submediterranean belt: rather rare

Padanian area: extremely rare

Humid submediterranean belt: very rare

Humid mediterranean belt: very 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

Herbarium samples

Smithsonian Institution, National Museum of Natural History, Department of Botany – CC BY-SA NC