Taxa described in 1803

Cetraria is a genus of fruticose lichens that associate with green algae as photobionts. Most species are found at high latitudes, occurring on sand or heath, and are characterised by their "strap-like" form with spiny edges. The lobes can range from narrow and linear to broader and flattened, often forming loose or densely packed cushions. Their distinctive spiny margins serve both a defensive role and aid in vegetative reproduction through fragmentation. The genus was created by Erik Acharius in 1803 and belongs to the large family Parmeliaceae. While originally a species-rich genus, taxonom

genus of fungi

Lepraria is a genus of leprose (powdery) crustose lichens that grows on its substrate like patches of granular, caked up, mealy dust grains. Members of the genus are commonly called dust lichens. The main vegetative body (thallus) is made of patches of soredia (little balls of algae wrapped in fungus). Sexual structures have not been observed in Lepraria, but genomic evidence indicates that the genus retains mating type and meiosis-associated genes, raising the possibility of cryptic sexual or parasexual recombination. Some species can form marginal lobes and appear squamulose. Because of the

Lecidea is a genus of crustose lichens with a carbon-black ring or outer margin (exciple) around the fruiting body disc (apothecium), usually (or always) found growing on (saxicolous) or in (endolithic) rock. Lichens that have such a black exciple are called lecideine, meaning "like Lecidea, even if they are not in this genus. Members of the genus are commonly called disk lichens or tile lichens.

Pyrularia is a small genus of shrubs or small trees in the sandalwood family (Santalaceae) which contains two species, Pyrularia pubera and Pyrularia edulis. P. pubera grows in the eastern United States and P. edulis grows in Bhutan, China, India, Myanmar, and Nepal. Both species are parasitic plants, specifically hemiparasites, which while still photosynthetic, will also parasitize the roots of other plants around them.

Thelotrema is a genus of lichen-forming fungi in the family Graphidaceae, the family to which all taxa in the former Thelotremataceae now belong.

Psoroma is a genus of lichen-forming fungi in the family Pannariaceae. The widespread genus contains about 30 species, most of which are found in south temperate regions.

genus of plants

Centrotus is a genus of mostly Palaearctic treehoppers belonging to the family Membracidae. Common European species include the type species Centrotus cornutus (widespread including Scandinavia and the British Isles) and C. chloroticus (southern France and the Iberian peninsula).

Bathelium is a genus of lichen-forming fungi in the family Trypetheliaceae.

genus of insects