Primary thallus: squamulose, persistent; squamules: 3-10 mm long, 1-5 mm wide, lead-gray above, conspicuously white below; surface: papillate and maculate, often somewhat pruinose podetia: rare, 5-25 mm tall, 1-4 mm thick, gray, stoutish, club-like or slightly branched at tips, without cups surface: areolate-corticate, pruinose, esorediate, verruculose, grooved Apothecia: common on podetia, 2-4 mm wide, dark brown, pruinose ascospores: not observed Pycnidia: frequent, on primary squamules, globose to broadly conical, large (to 400 micro meter thick), constricted at base, with hyaline gelatin conidia: not observed Spot tests: K+ pale yellow to golden yellow, or slowly red, C-, KC-, P+ yellow, or slowly red, UV- Secondary metabolites: having several chemotypes but in our area only one with atranorin and psoromic acid known; other chemotypes (Huovinen et al. 1989) are expected. Habitat and ecology: on calcareous or otherwise base-rich soil, also on mossy, calcareous rocks World distribution: Asia, Europe, North America and South America, from polar to temperate regions Sonoran distribution: eastern and northern Arizona. Notes: This species (often misspelled C. symphycarpa, see Ahti 2000: 266) has been overlooked and confused in North America, apparently because it is normally found in the sterile, non-podetiate stage only. It is expected to be more widespread than indicated here, particularly in limestone areas. All the Arizona material recorded (preserved in MIN) represents the psoromic acid chemotype, which is frequently (e.g., Hammer 1995) recognized as a distinct species, C. dahliana, but following Harris (1975b) and Huovinen and Ahti (1989), we include the material in C. symphycarpia. Large morphs of C. cariosa are difficult to distinguish from C. symphycarpia and C. macrophyllodes, both of which occur on acidic substrates and frequently lack podetia.