Lichenochora

Lichenochora fungi form tiny, flask-shaped reproductive structures called perithecia that are typically 0.15-0.3 mm in diameter. The perithecia are embedded within small swellings or galls that they cause to form in their host lichen's body (thallus). Only the dark-coloured openings of these structures are visible on the surface.^[4]

The walls of the perithecia are brown in colour and made up of several layers of flattened cells. Inside each perithecium are microscopic sac-like structures called asci, which contain the fungal spores. A distinctive feature of Lichenochora is that each ascus contains either four or eight spores, depending on the species. The spores themselves are colourless (hyaline) and divided into two cells.^[4]

Another characteristic feature is the presence of numerous oil droplets (lipid droplets) within various parts of the fungal structure, including the spores and the tissue surrounding them. The genus also has specialised filaments called periphyses around the opening of the perithecia, which often have swollen outer walls and may be slightly brown at the tips.^[4]

All known species of Lichenochora are highly specific about which lichens they parasitise, with most species only growing on particular genera or species of lichens. They show a particular preference for lichens in the family Physciaceae. While these fungi are technically parasites, they typically do not severely damage their host lichens, though they may cause some localised tissue death and discolouration where they grow. The species in the can be distinguished from each other by characteristics such as spore size and shape, the number of spores per ascus, and which lichen species they parasitise.^[4]

As of February 2025^[update], Species Fungorum (in the Catalogue of Life) accept 47 species of Lichenochora:^[5]