Thelenella Nyl. (1855)

Data Set Maintenance: Data set standard item. Data set author(s): Rambold G. Data set reviewer(s): Aptroot A. (95-02-18) and Scholz P. (02-05-17); revised; to be published after submission.

Nomenclature: Current taxonomic status: accepted or basionymous. Taxonomic rank: genus. Number of known taxa within this rank: 20. Thelenella. Thelenellaceae H. Mayrhofer (1986); Pyrenulales.

Type Information: Type: Thelenella modesta (Nyl.) Nyl.

Taxonomic Literature: Kalb K. in: Daniels F.J.A., Schulz M. & Peine J. (eds): Flechten
Follmann: 249-253, Cologne (1995); Mayrhofer H., Biblioth. Lichenol.
26: 1-106 (1987); Mayrhofer H. in: Nash T.H. III et al. (eds) Lichen Flora of the Greater Sonoran Desert Region vol. 1, 479-481, Tempe (2002); Purvis O.W. & James P.W. in: Purvis O.W. et al. (eds), The Lichen Flora of Great Britain and Ireland, London (1992).

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

Ecology: Biotroph; lichenized; corticolous; substrate non-calciferous.

Lichen Photobionts: Primary photobiont present; chlorococcal. Secondary photobiont absent.

Thallus: Indistinct or crustose, not subdivided parts, granular, rimose, or areolate (primarily areolate). Upper Surface: Grey, green, or brown; special structures absent. Lower Surface: Attached by the whole lower surface; special structures absent.

Reproduction Strategy: Only known as sterile, asexually reproducing form or with sexual (and possible asexual) stages. Ascocarps: Perithecioid, orbicular, forming all across the thallus surface, not emerging (but appearing as prominent warts), becoming adnate. Wall: Not carbonized, not fused. Margin: Indistinct; external filaments absent. Exciple: White or brownish yellow. Periphyses: Absent. Interascal Hyphae: Present, distinctly branched, distinctly anastomosed.

Asci: Tholus thickened, not amyloid; ocular chamber indistinct; dehiscence bitunicate; exoascus not amyloid, not hemiamyloid.

Ascospores: 1–2 to c. 8 per ascus, ellipsoid, oblong, or fusiform, 20-42 µm long, 9-17 µm wide, obtuse; septa present; both transversally and longitudinally, formed by the proper spore wall; wall thin or thick, distinctly differentiated into primary and secondary wall, not thickened at the septum, hyaline or pale brown, in Lugol's Solution negative, wall not ornamented.

Conidiomata: Absent resp. not observed or present; pycnidial; immersed.

Conidia: Filiform.

Secondary Metabolites: Not detected.

(report generated 04.Okt.2007)