A key to the species of Gyalolechia from China

1 Thallus with schizidia.........................................................................................................................................................................2

- Thallus without schizidia....................................................................................................................................................................3

2 Thallus covered with whitish pruina ..................................................................................................................................................4

- Thallus without whitish pruina...........................................................................................................................................................5

3 Thallus almost foliose with distinctly lobate....................................................................................................................... G. fulgens

- Thallus areolate to squamulose ..........................................................................................................................................................6

4 Ascospores septate......................................................................................................................................................... G. desertorum

- Ascospores aseptate, single-celled ............................................................................................................................. G. subbracteata

5 Having granulose thallus ................................................................................................................................................... G. epiphyta

- Having an areolate to squamulose thallus ..........................................................................................................................................7

6 Upper surface smooth............................................................................................................................................... G. flavovirescens

- Upper surface farinose....................................................................................................................................................... G. farinosa

7 Marginal lobes distinct, upper cortex with numerous crystals ......................................................................................... G. pustutata

- Marginal lobe indistinct, upper cortex palisade-plechtenchymatous .............................................................................. G. bracteata