KEY TO THE GENERA JAPEWIA AND
JAPEWIELLA
1. Thallus sorediate................................. 2
1. Thallus esorediate................................ 3
2. Norstictic acid present, thallus K+yellow turning red and P+ yellow..... Japeaeiella dollŋpartoniana
2. Norstictic acid absent (no substances present, lobaric acid present, or secalonic acid A present), thallus K‾ and P‾........................... Japeaeia subaurifera Muhr & Tønsberg
3. Ascospores with a thick, multilayered wall that is Ẑ1.5 µm thick; exciple poorly developed and not differentiated from the hamathecium; atra- norin absent. Japeaeia tornoensis (Nyl.) Tønsberg
3. Ascospores with a thin, uniform wall that is Ś1.5 µm thick; exciple well developed and strongly differentiated from the hamathecium; atranorin and/or other substances present....... 4
4. Hypothecium and subhymenium Ś60 µm tall.. Japeaeiella carrollii (Coppins & P. James) Printzen
4. Hypothecium and subhymenium Ẑ100 µm tall.. 5
5. Proper exciple quickly excluded and not in- spersed with granules..................................... Japeaeiella djagensis (Zahlbr.) Printzen
5. Proper exciple persistent and inspersed with granules.......................................... 6
6. Crystals in the proper exciple soluble in K; thallus warty-areolate; atranorin and 3-chlorostenospor- ic acid, 3-chloroperlatolic acid, and 3-chlorodi- varicatic acid present.. Japeaeiella pacifica Printzen
6. Crystals in the proper exciple not soluble in K; thallus continuous and smooth; other combina- tions of substances present...................... 7
7. Apothecia small, Ś0.5 mm in diameter; atra- norin present...................................... Japeaeiella taυaresiana (H. Magn.) Printzen
7. Apothecia larger, 0.3–1.0 mm in diameter; pannarin and xanthones variably present but often difficult to detect............................ Japeaeiella pruinosula (Müll. Arg.) Kantvilas