Keys to the macrolichens and checklist of the lichens and ...

14a. Tenuiorin and methylgyrophorate absent but terpenoids present; upper surface
smooth, sometimes slightly pruinose at the margins or incrusted; lobes with raised
and crisped lateral margins ..................................................................... P. oceanica
14b. Tenuiorin and methylgyrophorate always produced, together with terpenoids..... 15
15a. Rhizines abundant, or rarely sparse, rather short, fasciculate or densely branched.
................................................................................................................................ 16
15b. Rhizines sparse or abundant, most usually long and simple.................................. 17
16a. Terpenoids present, mostly zeorin or peltidactylin but dolichorrhizin not produced
............................................................................................................P. dolichorhiza
16b. Terpenoids present, dolichorrhizin abundantly produced.....................P. sumatrana
17a. Thallus robust, not distinctly undulating; lower surface with a dense network of
unraised, dark veins with distinct rather small, elliptical, whitish interstices; upper
surface usually with pruina at the lobes margins and sometimes with large and
conspicuous incrusted patches; dolichorrhizin as the main terpenoid produced;
terricolous ......................................................................................................P. nana
17b. Thallus fragile, with a distinctly undulating surface with shallow depressions, at
least in well-developed specimens; lower surface with a loose network of raised,
pale to dark veins with large, ellipitical, whitish to pale orange interstices;
terpenoids produced in several chemotypes; mostly epiphytic, rarely on rotten
wood or on terricolous mosses...........................................................P. dolichorhiza
Phaeophyscia Key:
1a. Thallus without pigment in the medulla .................................................P. hispidula
1b. Thallus with medullary pigment .............................................................................. 2
2a. Medullary pigment yellow..........................................................................P. crocea
2b. Medullary pigment red................................................................. P. endococcinodes
Physcia Key:
1a. Thallus without vegetative propagules .................................................................... 2
1b. Thallus with isidia or soredia................................................................................... 3
2a. Thallus maculate, saxicolous ....................................................................... P. phaea
2b. Thallus not maculate, corticolous ..........................................................P. verrucosa
3a. Thallus with true isidia........................................................................... P. vermifera
3b. Thallus with soredia or isidioid soredia................................................................... 4
4a. Lower surface black................................................................................................. 5
4b. Lower surface white to brownish............................................................................. 6
5a. Lower surface striate, soredia mainly marginal....................................P. atrostriata
5b. Lower surface not striate.......................................................................................... 6
6a. Upper surface bluish pruinose, soredia punctiform ...................................P. krogiae