Ochrolechia

These lichens typically form uneven, often thick, crust-like growths on various surfaces and are characterised by their white to pale grey thalli, which may have a greenish tint.

The genus has a long evolutionary history, with fossils dating back to the Paleogene period, about 34 million years ago.

Ochrolechia species have disc-like apothecia (fruiting bodies), which are usually yellowish or brownish-pink and often covered with a fine white powdery coating.

The genus is widely distributed and includes both common and rare species, with some found in extreme environments such as arctic and alpine regions.

The family was initially conceived to include Ochrolechia and tentatively the Varicellaria and Variolaria groups of species that were formerly classified within the large genus Pertusaria.

In some cases, the thallus may appear as scattered, convex warts or, more rarely, as minutely shrubby due to the presence of tiny papillae or spine-like extensions.

The asci, or spore-producing cells, contain between two and eight spores, and have thick, amyloid walls, meaning they stain blue with iodine and are similar to those found in the genus Pertusaria.

Ochrolechia szatalaensis
Ochrolechia trochophora
Ochrolechia upsaliensis