The Flames   (18 genera)

Here belong all lichens having a bright yellow or orange thallus, regardless of growth form. (Note: For species consisting exclusively of yellow- or orange-rimmed apothecia, see the Button Lichens.)

The Gels   (45 genera)

Here belong all sombre-coloured cyanobacterial lichens that are dark within (i.e., lack a white medulla), regardless of growth form.

Pimple Crusts   (90 genera)

Here belong all crusty chlorolichens with pimple-shaped perithecia.

Script Crusts   (36 genera)

Here belong all crusty chlorolichens with elongate or branched apothecia.

Button Crusts   (169 genera)

Here belong all crusty chlorolichens with rounded apothecia (sometimes immersed).

Dust Crusts   (8 genera)

Here belong all powdery or fluffy crusty chlorolichens entirely lacking a cortex and rarely if ever bearing apothecia or perithecia.

The Scales   (31 genera)

Here belong all colonial squamulose chlorolichens and cyanolichens consisting of numerous tiny, mostly rather short “fish scales”.

The Navels   (11 genera)

Here belong all foliose chlorolichens with a white medulla and a single central point of attachment.

The Browns   (13 genera)

Here belong all foliose chlorolichens with a white medulla and distinctly brownish or blackish lobes.

The Leafs   (35 genera)

Here belong all foliose chlorolichens with a white (or coloured) medulla and short to elongate lobes somewhat shiny near the tips.

The Petals   (15 genera)

Here belong all foliose chlorolichens with a white medulla and distinctly elongate lobes dull and/or frosted near the tips.

The Mantles   (10 genera)

Here belong all foliose cyanolichens (and cephalodiate lichens) with a white medulla and broad, mostly rounded, loosely attached lobes.

The Underlays   (11 genera)

Here belong all foliose cyanolichens with a white medulla and more or less long, narrow, generally closely attached lobes, frequently with a fungal “underlay” when young.

The Stickpins   (19 genera)

Here belong crusty or squamulose chlorolichens (and honorary lichens) with small to tiny, erect capillary fruiting stalks and/or smudgeable spores.

The Clads   (2 genera)

Here belong Cladonia and its allies: you either know this group or you don't.

The Scrubs   (28 genera)

Here belong all club-like and shrub-like fruticose macrolichens or mesolichens with a white medulla (except the Clads).

The Hairs   (9 genera)

Here belong all hair-like fruticose macrolichens with a white medulla.

The Gossamers   (6 genera)

Here belong all hair-like fruticose mesolichens without a white medulla.

The Cling-ons   (63 genera)

Here belong all unlichenized fungi and lichens that routinely grow on or parasitize other lichens.

The Honoraries   (11 genera)

Here belong various additional fungi and algae that traditionally get studied by lichenologists.