Physconia isidiigera (Zahlbr.) Essl.

Data Set Maintenance: Data set authentic and standard item. Data set author(s): Esslinger T. (99-11-18). Data set not to be published after submission.

Nomenclature: Current taxonomic status: accepted. Taxonomic rank: species. Physconia. Physciaceae Zahlbr. (1898).

Taxonomic Literature: Esslinger, T., Mycotaxon 51: 91-99 (1994);.

Biogeography: Continent: Northern America. Checklist records: United States and Canada (continental).

Ecology: Lignicolous or corticolous; substrate non-calciferous or calciferous.

Thallus: Foliose, lobed; lobes linear; irregularly rounded at the front; concave or usually plane; separate thallus parts 1-2-(3) mm wide. Thallus Size and Differentiation: Up to 7 cm in diameter; apex not curved. Upper Surface: Grey or brown; pruinose; pruina usually abundant; often continuous or patchy; without hairs; not isidate; sorediate; soralia grey, brown, or grey-brown, peripheral (marginal on lobes), linear, isidiate (sometimes becoming almost like true isidia, but usually different in color and texture from main cortex), soredia coarse. Lower Surface: Black in the centre, brown or pale brown along the margin; rhizinate; rhizines moderately abundant, black, branched, squarrosely branched.

Upper Cortex: Outer cortical layer paraplectenchymatous. Medulla: White. Lower Cortex: Present; prosoplectenchymatous, of periclinal hyphae.

Reproduction Strategy: Only known as sterile, asexually reproducing form or with sexual (and possible asexual) stages. Ascocarps: Sparse, up to 2 mm in diam.. Margin: Very rarely lobulate; sorediate.

Ascospores: 28-38 µm long, 15.5-18 µm wide.

Secondary Metabolites: Not detected.

Spot Tests: Absent reactions.

(report generated 13.Nov.2007)