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. There are no known mechanisms for sexual reproduction, yet members of the genus continue to speciate. Some species can form marginal lobes and appear squamulose. Because of the morphological simplicity of the thallus and the absence of sexual structures, the composition of lichen products are important characters to distinguish between similar species in Lepraria.
Lepraria incana is a species of dust lichen in the family Stereocaulaceae. First described scientifically by Johann Jacob Dillenius in 1741, and then formally by Carl Linnaeus in 1753, it is the type species of the genus Lepraria. The thallus of this species is green to greyish-green, and powdery – as if made of tiny granules. These granules are soredia, which are asexual reproductive structures. Like most members of genus Lepraria, the lichen has few distinguishing features, lacking both a medulla and sexual reproductive structures (apothecia). Chemically, the lichen is characterised by the presence of the secondary chemicals known as divaricatic acid and zeorin.
Lepraria torii is a species of corticolous and lignicolous, leprose lichen in the family Stereocaulaceae. It is found in northwestern North America.
Lepraria bergensis is an uncommon crustose lichen in the family Stereocaulaceae. It occurs in Northern and Central Europe, where it grows on siliceous (silicon-rich) rock walls, particularly under small overhangs, and on mosses on vertical to slightly sloping rock surfaces. The lichen thallus forms as a pale bluish-grey crust-like growth on rocks and mosses. The lichen begins as small, rounded patches a few millimetres wide, which may eventually coalesce into larger areas exceeding 1 centimetre in diameter. The thallus has a powdery texture, consisting of minute granules known as soredia and consoredia, which facilitate the lichen's asexual reproduction. The chemical composition of Lepraria bergensis is distinguished by the presence of several secondary metabolites: atranorin, rangiformic acid or jackinic acid, trace amounts of their respective derivatives, and a variety of anthraquinones. These chemical components cause the lichen to fluoresce a dull yellow under long-wave ultraviolet light.
Lepraria atlantica is a species of leprose lichen in the family Stereocaulaceae. Described as a new species in 2001, the lichen occurs in Australia, Europe, and Greenland, where it typically grows over rocks and associated mosses.
Lepraria alpina is a species of leprose lichen in the family Stereocaulaceae. It is found in Europe, North and South America, Antarctica, and Greenland, where it typically grows on rocks and rock-dwelling mosses in cool habitats.
Lepraria celata is a species of leprose lichen in the family Stereocaulaceae. The powdery greyish-green lichen, described as a new species in 2006, occurs in eastern Europe.
Lepraria borealis is a species of leprose lichen in the family Stereocaulaceae, found in cool climates across Northern Europe, northwestern North America, Greenland, and Antarctica. It primarily grows on acidic rock and moss-covered surfaces, occasionally occurring on soil or other lichens. The species forms a granular crust with abundant soredia and shows considerable chemical variation, typically containing atranorin and rangiformic acid.
Leprocaulon coriense is a species of leprose lichen in the family Stereocaulaceae. It is found in Asia and Australia where it grows on various substrates, including rock, wood, bark, mosses and soil.
Lepraria cupressicola is a species of leprose lichen in the family Stereocaulaceae. It occurs in east and southeast Asia, where it grows on rocks, soil and bark in shaded, damp locations.
Lepraria diffusa is a species of leprose lichen in the family Stereocaulaceae. Originally described as Leproloma diffusum by Jack Laundon in 1989, it was reclassified into Lepraria in 2002. The lichen has a powdery thallus containing the secondary metabolite 4-oxypannaric acid 2-methylester. It grows on calcareous rocks and mosses in shaded areas across Asia, Europe, North America, and South America.
Lepraria eburnea is a widespread species of leprose lichen in the family Stereocaulaceae. It forms a powdery to cottony thallus that lacks clear boundaries and contains alectorialic acid as its main secondary metabolite. It grows on various substrates including rock, bark, and soil, showing a particular preference for calcareous materials in some regions. The lichen is found across Europe, North America, Australasia, and Greenland, occurring from sea level to alpine elevations, and is typically found in areas with high humidity. In North America, it is particularly abundant in the Great Lakes region and Maritime provinces of Canada, where it commonly grows as an epiphyte on tree bases in swampy areas.
Lepraria friabilis is a species of leprose lichen in the family Stereocaulaceae. It has a disjunct distribution in the southeastern United States and southern California, where it grows exclusively on coniferous bark in humid environments such as swamps and stream valleys.
Lepraria gelida is a species of leprose lichen in the family Stereocaulaceae. It occurs in Greenland, Svalbard and the Russian Arctic islands, where it grows on soil, mosses and sometimes lichens, and rarely on bark.
Lepraria goughensis is a little-known species of leprose lichen in the family Stereocaulaceae. It is only known to occur on Gough Island in the south Atlantic Ocean.
Lepraria impossibilis is a species of leprose lichen in the family Stereocaulaceae. It forms a powdery to membranous thallus with a well-defined margin and distinctive secondary metabolites, including lecanoric acid and pannaric acid 6-methylester. The species is morphologically similar to Lepraria cupressicola and L. vouauxii but can be distinguished by its chemical composition. Lepraria impossibilis grows on tree bark, mosses, and soil-covered rocks, occurring in forested and open habitats across South and Central America, including El Salvador, Bolivia, Chile, and Peru, as well as in Iran.
Lepraria jackii is a species of leprose lichen in the family Stereocaulaceae, described by Tor Tønsberg in 1992. It forms a powdery thallus with variable colouration, ranging from pale green to straw-coloured, and grows on bark, mosses, wood, and rock surfaces in humid, sheltered environments. The species is characterised by its abundant soredia and distinctive secondary metabolites, including atranorin. Lepraria jackii has been recorded across Europe, North America, Asia, and Australia, preferring acidic substrates.
Lepraria leuckertiana is a species of leprose lichen in the family Stereocaulaceae. It occurs in Europe, North Africa, and South America, where it grows on bark and occasionally on soil in humid, open, well-lit places.
Lepraria lobata is a species of leprose lichen in the family Stereocaulaceae. It is found in Australia, where it grows on bark, mosses on rock, and soil.
Lepraria lecanorica is a species of leprose lichen in the family Stereocaulaceae. It occurs in North and South America, where it grows on bark, rock, and soil substrates, typically in shaded locations.
