Arthothelium A. Massal. (1852)

Data Set Maintenance: Data set standard item. Data set author(s): Rambold G. Data set reviewer(s): Grube M. (95-12-05) and Triebel D. (00-06-29); revised; to be published after submission.

Nomenclature: Current taxonomic status: accepted or basionymous. Taxonomic rank: genus. Number of known taxa within this rank: 80. Arthothelium. Arthoniaceae Reichenb. (1841); Arthoniales.

Type Information: Type: Arthothelium spectabile (Flot.) Massal.

Taxonomic Literature: Clauzade G. & Roux C., Bull. Soc. Bot. Centre-Ouest N.S. - Numero
Special 7: 1-893 [171-174] (1985); Coppins B.J., Lichenologist 21:
195-216 (1989); Coppins B.J. in: Purvis O.W. et al. (eds), The Lichen
Flora of Great Britain and Ireland, London (1992); Coppins B.J. &
Tønsberg T., Nord. J. Bot. 4: 75-77 (1984); Galloway D.J.,
Flora of New Zealand Lichens: i-lxxiii, 1-662 [17- 20], Wellington
(1985); Grube M. & Giralt M., Lichenologist 28: 15-26 (1996);
Ihlen P.G. & Coppins B.J., Nova Hedwigia 69(3-4): 391-397 (1999);
Makhija U. & Patwardhan P.G., Lichenologist 29: 169-172 (1997);
Santesson R., Symb. Bot. Upsal. 12: 1-590 [92-94] (1952); Tehler A.,
Can. J. Bot. 68: 2458-2492 (1990).

Biogeography: Checklist records: Austria, Germany, Great Britain, Guianas, Italy, New Zealand, Sonoran Desert, Sweden and Norway, Thailand, United States and Canada (continental), and Republic of South Africa.

Ecology: Saprobic or biotroph; lichenized; corticolous.

Lichen Photobionts: Primary photobiont absent or present; chlorococcal and trentepohlioid. Secondary photobiont absent.

Thallus: Indistinct or crustose, not subdivided parts. Upper Surface: White; special structures absent. Lower Surface: Attached by the whole lower surface; special structures absent.

Medulla: Iodine reaction in Lugol's solution positive.

Reproduction Strategy: Only known as sterile, asexually reproducing form or with sexual (and possible asexual) stages. Ascocarps: Apothecioid, irregular or linear, not emerging, becoming adnate. Margin: Indistinct to distinct. Epithecium: Apical cells yellow or brown. Hymenium: Iodine reaction: Lugol’s negative, not hemiamyloid or hemiamyloid. Interascal Hyphae: Present, distinctly branched, distinctly anastomosed. Hypothecium: Brown.

Asci: Ocular chamber indistinct or broad; dehiscence bitunicate; exoascus not hemiamyloid or hemiamyloid.

Ascospores: c. 4 to c. 8 per ascus, ellipsoid, ovoid, clavate, or oblong, 15-90 µm long, 7-28 µm wide, obtuse or aciculate; septa present; both transversally and longitudinally, 2-10-transversally septate, formed by the proper spore wall; wall thin, not thickened at the septum, hyaline or pale brown, in Lugol's Solution negative, wall not ornamented.

Conidiomata: Absent resp. not observed or present.

Secondary Metabolites: Not detected or present, of the following substance class(es): benzyl esters and xanthones.

(report generated 04.Okt.2007)