ITALIC 7.0

Arthonia molendoi (Frauenf.) R. Sant.

Thunbergia, 3: 2, 1986. Basionym: Tichothecium molendoi Frauenf. - in Arnold, Verh. zool. bot. Ges. Wien, 14: 461, 1864.

Synonyms: Arthonia molendoi (Arnold) R. Sant.; Bryostigma molendoi (Heufl. ex Arnold) S. Y. Kondr. & J.-S. Hur

Distribution: N - Frl (TSB 5100 as A. clemens), TAA (Nimis & Tretiach 1999, Brackel 2008, 2011, 2015, 2016), VA (Hafellner 2021), Lig (Ravera & al. 2022). C - Tosc (Herb. von Brackel 393), Marc (Herb. von Brackel 390), Umb (Herb. von Brackel 394), Laz (Herb- von Brackel 389), Abr (Nimis & Tretiach 1999, Brackel 2015, 2016, 2020). S - Bas (Brackel 2016, 2020), Si (Herb. von Brackel 392).

Description: Thallus inapparent, not lichenized, the hyphae developing inside the thalli of crustose and foliose Teloschistaceae. Apothecia arthonioid, immarginate, single or in groups of up to 5(-10) per infection spot, sometimes coalescent, developing in the cortex of the host, more or less round, adnate, 0.1-0.3 mm across, with a jet black, convex disc, without a proper margin. Proper exciple poorly developed; epithecium blackish brown with a dark olivaceous tinge, 15-20 µm high, K-; hymenium colourless to pale brown, up to 45 µm high, I+ red, K/I+ blue; paraphysoids branched and anastomosing, c. 2 µm thick, the apical cells up to 4 µm wide; hypothecium colourless to pale yellow, 50-60 µm high. Asci 4-8-spored, broadly clavate to subglobose, semi-fissitunicate, with a large, non-amyloid apical dome, and a distinct ocular chamber, Arthonia-type. Ascospores 1-septate, one cell slightly attenuated, hyaline, 8-13 x 4-6 µm, with a gelatinous epispore. Photobiont absent. Spot tests: K-, C-, KC-, P-. Chemistry: without lichen substances.

Note: a widespread, holarctic and bipolar lichenicolous fungus which in Italy is most frequent on the type host Rusavskia elegans, and on Xanthomendoza- and Calogaya-species; earlier records reported as growing on Xanthoria parietina refer to the recently-described Arthonia parietinaria (see Fleischhacker & al. 2016 and Brackel 2020).

Growth form: Lichenicolous fungus

Substrata: rocks

Reproductive strategy: mainly sexual

paras Xanthoria spp. and Caloplaca s.lat. spp.

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: very rare

Oromediterranean belt: absent

Montane belt: rather rare

Submediterranean belt: very 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

Index Fungorum GBIF

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (24445)
2003/01/23
on the thallus of the host, Xanthoria elegans

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (24445)
2003/01/23
on the thallus of the host, Xanthoria elegans