Coccotrema inactivum Fryday ad int.
Synonym: Coccotrema mammatum (Nyl). Imshaug in sched. non Pertusaria mammata Nyl.
Thallus covered with irregular isidia to 1.2 x 0.3 mm
Ascospores: (50-)70-88(-100) x (24)28.5-32.5Ám; 2/ascus
Chemistry: no substances by tlc
Corticolous; numerous collections from southern South America (Patagonian Channels to Isla de los Estados).
Notes: Imshaug was calling this taxon C. mammatum (Nyl.) comb. nov. However, although the holotype of Pertusaria mammata Nyl. (in H-Nyl.) is very small, asospore details are indicated on the packet as 56-70 x 30-35 µm and 8/ascus. It has a thallus of large, corticate granules, has been TLC'd (by M. Oshio in 1974) and found to contain stictic and constictic acids. It was annotated as C. cucurbitula by Rolf Santesson in 1959, which is clearly correct.
Coccotrema inactivum is similar to C. magellanicum but with larger spores, 2/ascus, and with a thallus lacking lichen substances and soredia.