Pseudotichia

Pseudotichia is a fungal genus in the family Lichinaceae. It comprises the single species Pseudotichia vermiculata, a cyanolichen. Originally described in 1881 from material collected near Budapest, the species was later placed in Psorotichia before molecular studies demonstrated it represents a separate evolutionary line. It grows on calcareous rocks that are periodically wetted by seeping water, favouring exposed limestone surfaces. The lichen can be recognised by its dark, cracked crust with mostly embedded fruiting bodies and a distinctive cottony layer of fungal filaments anchoring it to the rock substrate.

Taxonomy

The genus Pseudotichia was introduced to hold a single species, Pseudotichia vermiculata, which had long been known under other names. The species was originally described in 1881 by William Nylander, who introduced it as Collemopsis vermiculata on the basis of material collected by Hugó Lojka from dolomitic rock near Budapest; he characterised it as a dark, sooty to brown-black, tile-cracked crustose lichen with immersed brown apothecia and simple ellipsoid spores, and noted its similarity to C. caesia. A few years later (1885), it was later transferred to Psorotichia as Psorotichia vermiculata. Molecular work has shown that it does not belong with Psorotichia in the strict sense but instead forms a separate lineage within Lichinaceae, warranting recognition of a new genus. The generic name refers to this history: Pseudotichia is named for its overall resemblance to Psorotichia, with the prefix "pseudo-" indicating that the similarity is superficial rather than reflecting a close relationship.