Sarcogyne is a genus of crustose lichens in the family Acarosporaceae. It was circumscribed by German botanist Julius von Flotow in 1850. A proposal has been put forth in 2021 to assign Sarcogyne clavus as the type species of the genus, "as it represents the original concept of Sarcogyne as having melanized lecideine apothecia without algae in the margin".
Peltula is a genus of small dark brown to olive or dark grey squamulose lichens. These lichens typically grow on rocks in arid and semi-arid environments worldwide. They consist of a fungus living in symbiosis with a photosynthetic partner, specifically a cyanobacterium of the genus Chroococcidiopsis. Peltula is the only genus in the family Peltulaceae, which belongs to the Lichinomycetes, a class of fungi that form lichens. The genus includes about 50 recognised species, which exhibit a variety of growth forms ranging from flat and crust-like to more complex, leaf-like structures. Peltula lichens play important ecological roles in harsh environments, contributing to soil stability and nutrient cycling.
Acarospora flavisparsa is a species of lichen in the family Acarosporaceae. Found in Portugal and Spain, it was described as new to science in 2011. The lichen grows on acidic rock walls in inland areas.
Crustose lichens are lichens that form a crust which strongly adheres to the substrate, making separation from the substrate impossible without destruction. The basic structure of crustose lichens consists of a cortex layer, an algal layer, and a medulla. The upper cortex layer is differentiated and is usually pigmented. The algal layer lies beneath the cortex. The medulla fastens the lichen to the substrate and is made up of fungal hyphae. The surface of crustose lichens is characterized by branching cracks that periodically close in response to climatic variations such as alternate wetting and drying regimes.
Lichens are symbiotic organisms made up of multiple species: a fungus, one or more photobionts and sometimes a yeast. They are regularly grouped by their external appearance – a characteristic known as their growth form. This form, which is based on the appearance of vegetative part of the lichen, varies depending on the species and the environmental conditions it faces. Those who study lichens (lichenologists) have described a dozen of these forms: areolate, byssoid, calicioid, cladoniform, crustose, filamentous, foliose, fruticose, gelatinous, leprose, placoidioid and squamulose. Traditionally, crustose (flat), foliose (leafy) and fruticose (shrubby) are considered to be the three main forms. In addition to these more formalised, traditional growth types, there are a handful of informal types named for their resemblance to the lichens of specific genera. These include alectorioid, catapyrenioid, cetrarioid, hypogymnioid, parmelioid and usneoid.
Placolecis kunmingensis is a species of saxicolous (rock-dwelling), crustose lichen in the family Catillariaceae. It is found in Yunnan, China. The lichen is characterised by a thallus that is areolate to squamulose in its centre, forming irregular patches or clumps 10–50 mm wide, as well as its ellipsoid or spherical ascospores with slightly thickened wall.
Placolecis sublaevis is a species of saxicolous (rock-dwelling), crustose lichen in the family Catillariaceae. It is found in Yunnan and Sichuan, China. The crust-like, radiating body of the lichen forms irregular patches or clumps and includes numerous false conidiomata, a type of asexual reproductive structure, within its thallus. Its lobes, dark brown and slightly flattened at the top, form larger groups at the edges and contain an upper layer composed of loosely interwoven cells and a lower inner tissue that varies from reddish-orange to white.
Teloschistes spinosus is a species of corticolous (bark-dwelling), fruticose lichen in the family Teloschistaceae. It is found in Australia and New Zealand.
Austroparmeliella is a genus of lichen-forming fungi in the family Pannariaceae. It consists of five species, all of which are found in the Southern Hemisphere.
Romjularia is a fungal genus in the family Lecideaceae, containing the single species Romjularia lurida, a saxicolous and terricolous squamulose lichen.
Siphulastrum is a genus of lichen-forming fungi in the family Pannariaceae. It has five species. The genus was circumscribed by Johannes Müller Argoviensis in 1889, with S. triste assigned as the type species.
Boreoplaca is a fungal genus in the family Ophioparmaceae. It comprises the single species Boreoplaca ultrafrigida, a saxicolous (rock-dwelling), squamulose lichen. Both the genus and species were described in 1994 by the Norwegian lichenologist Einar Timdal. The lichen is found in Eastern Siberia, the Russian Far East as well as in adjacent territories of north-east China, and in South Korea. The main characteristics of the lichen are its squamulose thallus, black lecideine apothecia, and Fuscidea-type asci.
Acarospora stapfiana, the hoary cobblestone lichen, is a lichenicolous (lichen-dwelling) lichen species in the family Acarosporaceae. It is known for its parasitic relationship with members of the genus Caloplaca. The species has a unique life cycle in which it starts as a juvenile non-lichenised fungus before forming a fully lichenised thallus. It is found in Asia and North America, where it grows on calcareous rocks.
Nebularia is a small genus of lichen-forming fungi in the family Pannariaceae. It comprises two species, both of which are found in the Andes.
Pseudopeltula is a genus of lichen-forming fungi in the family Gloeoheppiaceae. Established in 1995 by the lichenologist Aino Henssen, the genus currently includes four recognised species. These small cyanolichens are characterised by their squamulose (scaly) to peltate (shield-shaped) thalli, which lack a lower cortex and are attached to the substrate by rhizines. A key feature of Pseudopeltula is its complex apothecia, which have hymenia that often become divided by sterile tissue as they mature. The genus is primarily found in arid and semi-arid regions of North America, Mexico, and the Caribbean, where species typically grow on soil, rock, or thin soil over rock, often forming part of biological soil crusts in desert environments.
Parallopsora is a small genus of lichen-forming fungi in the family Ramalinaceae. Established in 2018, the genus contains three species that were previously classified under a related genus, Phyllopsora. These lichens form small, scale-like growths that overlap like roof tiles and typically appear pale green to bluish-green in colour. They reproduce through both small brown fruiting bodies and sometimes through powdery structures on their surface. The species are known to grow in tropical rainforests, particularly in Brazil, Peru and Cuba.
Peltula polycarpa is a species of saxicolous (rock-dwelling), squamulose lichen in the family Peltulaceae. First described in 2022, it is endemic to Beijing's Mentougou District in China.
Peltula polyphylla is a ground-dwelling, squamulose lichen species in the family Peltulaceae, characterised by its distinctive multi-lobed structure. Found in China, it was described as a new species in 2022.
Peltula pseudoboletiformis is a species of saxicolous (rock-dwelling), squamulose lichen lichen in the family Peltulaceae, described in 2022. It is noted for its resemblance in thallus structure to the mushroom-forming fungal genus Boletus, which is reflected in its name.
Peltula submarginata is a species of saxicolous (rock-dwelling), squamulose lichen in the family Peltulaceae, first described in 2022. It occurs in China.
