''Lecanora'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, USDA Natural Resources Conservation Service Name Search
/ref> Lichens in the genus ''

Squamarina ''Squamarina'' is a genus of lichens in the family Stereocaulaceae. They form patches of radiating or overlapping scales (), with a well-developed upper and no lower cortex. They grow on calcareous soil and rocks. '' Squamarina lentigera'' c ...

'' are also called rim lichens. Members of the genus have roughly circular fruiting discs (

apothecia An ascocarp, or ascoma (: ascomata), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. As ...

) with rims that have photosynthetic tissue similar to that of the nonfruiting part of the lichen body (

thallus Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

). Other lichens with apothecia having margins made of thallus-like tissue are called lecanorine. It is in the family

Lecanoraceae The Lecanoraceae are a family of lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the c ...

in the suborder Lecanorineae.

Description

''Lecanora'' has a

crustose Crustose is a Habit (biology), habit of some types of algae and lichens in which the organism grows tightly appressed to a substrate, forming a biological layer. ''Crustose'' adheres very closely to the Substrate (biology), substrates at all poin ...

photobiont A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship.

, colourless

ascospore In fungi, an ascospore is the sexual spore formed inside an ascus—the sac-like cell that defines the division Ascomycota, the largest and most diverse Division (botany), division of fungi. After two parental cell nucleus, nuclei fuse, the ascu ...

s and crystals in the amphothecium. Swiss lichenologist Rosmarie Honegger used

electron microscopy An electron microscope is a microscope that uses a beam of electrons as a source of illumination. It uses electron optics that are analogous to the glass lenses of an optical light microscope to control the electron beam, for instance focusing i ...

in the late 1970s to investigate

ascus An ascus (; : asci) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some gen ...

structure in several major groups of lichen-forming fungi. She defined the ''Lecanora''-type ascus as one characterized by several distinctive features: (1) a non-

amyloid Amyloids are aggregates of proteins characterised by a fibrillar morphology of typically 7–13 nm in diameter, a β-sheet secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the human ...

, clear ascus wall that is encased in an amyloid outer layer often described as a ; (2) an amyloid filled with inclusions set within a clear matrix; (3) a clear central layer inside the dome; and (4) a method of opening, or dehiscence, that is rostrate (resembling the shape of a bird's beak – the ascus has a pointed or protruding tip from which the spores are released).

Species

:A 2008 estimate placed over 550 species in the genus. As of July 2022, ''

Index Fungorum ''Index Fungorum'' is an international project to index all formal names (scientific names) in the fungus kingdom. As of 2015, the project is based at the Royal Botanic Gardens, Kew, one of three partners along with Landcare Research and th ...

'' lists 245 species in the genus. *''

Lecanora campestris ''Lecanora'' is a genus of lichen commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichens in the genus '' Squamarina'' are also called rim lichens. Members of the genus have roughly c ...

'' (Schaer.) Hue 1888 *''

Lecanora conizaeoides ''Lecanora'' is a genus of lichen commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichens in the genus '' Squamarina'' are also called rim lichens. Members of the genus have roughly c ...

'' Nyl. ex Cromb. 1885Mycobank: Lecanora conizaeoides
/ref> *''

Lecanora gangaleoides ''Lecanora gangaleoides'' is a species of crustose lichen in the family Lecanoraceae The Lecanoraceae are a family of lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha ...

'', Nyl. 1872 *''

Lecanora grantii ''Lecanora'' is a genus of lichen commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichens in the genus '' Squamarina'' are also called rim lichens. Members of the genus have roughly c ...

'', H. Magn. 1932 *''

Lecanora helicopis ''Lecanora'' is a genus of lichen commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichens in the genus '' Squamarina'' are also called rim lichens. Members of the genus have roughly c ...

'', (Wahlenb. ex Ach.) Ach. 1814 *''

Lecanora mellea ''Lecanora mellea'' is a species of crustose lichen in the family Lecanoraceae The Lecanoraceae are a family of lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, fila ...

'', W.A.Weber (1975) *''

Lecanora muralis ''Lecanora muralis'' ''(Protoparmeliopsis muralis)'' is a waxy-looking, pale yellowish-green crustose lichen, crustose lichen that usually grows in rosette (botany), rosettes radiating from a center (placoidiod, placodioid) filled with disc-like ...

'', (Schreb.) Rabenh. (1845) *''

Lecanora poliophaea ''Lecanora'' is a genus of lichen commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichens in the genus '' Squamarina'' are also called rim lichens. Members of the genus have roughly c ...

'', (Wahlenb.) Ach. 1810 *''

Lecanora rupicola ''Lecanora rupicola'' is a species of crustose lichen in the family Lecanoraceae The Lecanoraceae are a family of lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, fi ...

'', (L.) Zahlbr. 1928 *''

Lecanora straminea ''Lecanora'' is a genus of lichen commonly called rim lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, Lichens in the genus '' Squamarina'' are also called rim lichens. Members of the genus have roughly c ...

'', Wahlenb. ex Ach. *''

Lecanora strobilina ''Lecanora strobilina'', also known as the mealy rim lichen, is a species of crustose lichen in the family Lecanoraceae. It was originally described as ''Parmelia strobilina'' by German botanist Kurt Polycarp Joachim Sprengel in 1827. It is dis ...

'', (Spreng.) Kieff. 1895 *'' Lecanora usneicola'', Etayo, 2006

Gallery

Image:Lecanora_strobilina_(EU).jpg, ''

'' Image:Lichen_on_the_riverside.jpg, ''Lecanora'' cf. ''muralis'' lichen on the banks of the Bega canal in Timișoara Image:Lecanora.Alan.JPG, ''Lecanora'' from coastal California

References

Lecanorales genera Lichen genera Taxa described in 1809 Taxa named by Erik Acharius {{Lecanorales-stub