#physciaceae

Powdered Fringe Lichen (Heterodermia speciosa), family Physciaceae

On a stone wall at the old Canterbury College, later the University of Canterbury.

First described by the French lichenologist and cleric Henri Jacques François Olivier in 1882.

A common, widely distributed lichen, found growing on stone or bark under a wide range of conditions, and one of the first lichens to colonise new substrate. Since it can reprout after passing through the digestive track of a snail, it's possible it has help getting around.

Physcia means bladder or blister, but it's not actually clear which part of the lichen the original taxonomist was thinking about.

A widespread lichen genus, most diverse in South America, and usually growing on bark, bare woofd, and stone, and more rarely on human structures. That said, they have rapidly recolonised urban areas previously scorched by acid rain.