Rusavskia elegans (Link) S. Y. Kondr. & Kärnefelt (Link) Th. Fr.
Ukr. Bot. Zh. 60, 4: 434 (2003).
Basionym: Lichen elegans Link, Ann. Nat. Urgesch. 1: 37 (1791).
Description: Lichen. Thallus foliose, forming small to large rosettes up to 6 cm wide or larger colonies, tightly adnate, lobate; lobes dorsiventral, convex, 0.4-1.3 mm wide; tips 0.3-0.7 mm wide, rotund to truncate; upper surface yellow to orange (to dull red), mostly somewhat coarse, occasionally slightly pruinose, esorediate; medulla white, reticulate, with short to elongate hyphae; lower surface white somewhat wrinkled, rarely with very short, white hapters. Apothecia common (sometimes lacking), laminal, stipitate, up to 3 mm in diam.; margin smooth or crenulate; disc orange; epihymenium brown, c. 10 µm thick; hymenium hyaline below, 60-90 µm tall; hypothecium hyaline to pale brown, 20-80 µm thick; paraphyses simple or branched, cylindrical, septate; asci clavate, 8-spored. Ascospores ellipsoid, polarilocular, hyaline, 11-18 x 5.5-8.5 µm; septum 1-5 µm wide. Pycnidia rare or common, immersed, slightly darker than upper surface; conidia ellipsoid, 2-3.5 x 1-1.5 µm. (Nash et al. 2001: xx).
Photobiont: Green alga.
Chemistry: Upper surface K+ purple, C-, KC-, P-; parietin (major), fallacinal, emodin, teloschistin, parietinic acid. (Nash et al. 2001: xx).
Ecology: On rock, in microclimate varying from humid to dry (author ?). The species has to be regarded as an indicator of airborne nitrogen deposition (Søchting 1989: 167).