[2] It is a monotypic genus, containing the single species Timdalia intricata, a saxicolous (rock-dwelling), crustose lichen.

This species was first formally described by Swedish lichenologist Adolf Hugo Magnusson in 1935, based on a collection made by Eduard Frey in Austria.

It was initially placed in the family Lecanoraceae,[4] but molecular phylogenetic studies showed Timdalia to belong in the Acarosporaceae.

[4] Later collections of Timdalia intricata were made in the Austrian Alps, Italy,[6] and various Scandinavian locations.

In Scandinavia, the lichen is usually found at subalpine and alpine elevation ranges between 630 and 1,400 m (2,070 and 4,590 ft), typically on vertical to overhanging rock faces, and on iron-containing silicate rocks.