Lobaria  

Thallus foliose, dorsiventral, irregularly spreading; lobes branched, the apices rounded or truncate, often incised. Upper surface smooth, flat or wrinkled, sometimes with distinct depressions with a network of ridges. Soredia and isidia occasionally present. Cortex pseudoparenchymatous. Photobiont green algae Dictyochoropsis or Trebouxia or cyanobacteria (Nostoc or Scytonema), the blue-green sometimes in internal or shrubby, external cephalodia. Lower surface tomentose; rhizines present, simple to squarrose. Pseudocyphellae and cyphellae absent.

Ascomata apothecia, rather rare. Thalline exciple present. Asci 8-spored, Peltigera-type. Ascospores colourless or pale brown, 1- to 7-septate, fusiform to elongate.

Conidiomata pycnidia, immersed, pimple-like, ostiole brown-black. Conidia cylindrical-elongated, slightly swollen at both ends.

Chemistry: depsides, depsidones.