''Placolecis'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of lichen-forming

fungi A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified ...

in the family

Catillariaceae The Catillariaceae are a family of crustose lichens in the order Lecanorales. Species of this family have a widespread distribution, especially in temperate areas. The family was originally circumscribed by Austrian lichenologist Josef Hafellner ...

. It has four species of

saxicolous A saxicolous lichen is a lichen that grows on rock. The prefix "sax" from the Latin means "rock" or "stone". Characteristics Saxicolous lichens exhibit very slow growth rates. They may develop on rock substrates for long periods of time, giv ...

(rock-dwelling) and

crustose lichen Crustose lichens are lichens that form a crust which strongly adheres to the substrate (soil, rock, tree bark, etc.), making separation from the substrate impossible without destruction. The basic structure of crustose lichens consists of a cor ...

s. The genus was

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every po ...

by Italian botanist

Vittore Benedetto Antonio Trevisan de Saint-Léon Vittore Benedetto Antonio Trevisan de Saint-Léon (5 June 1818, in Padua – 8 April 1897, in Milan) was an Italian botanist who specialized in cryptogamic flora. During his career, he was a professor of natural history in Padua. In 1882 he ...

in 1857. He did not assign a

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

for the genus.

Josef Hafellner Josef Hafellner (1951– ) is an Austrian mycologist and lichenologist. He was awarded the Acharius Medal in 2016 for his lifetime contributions to lichenology. Before his retirement, he was a professor at the Karl-Franzens-Universität in Gra ...

designated a

lectotype In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...

for ''Placolecis balanina'' in 1984, but subsequently, this

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

was folded into '' P. opaca''.

Species

*''

Placolecis kunmingensis ''Placolecis'' is a genus of lichen-forming fungi in the family Catillariaceae. It has four species of saxicolous lichen, saxicolous (rock-dwelling) and crustose lichens. The genus was circumscription (taxonomy), circumscribed by Italian botanis ...

'' – China *''

Placolecis loekoesiana ''Placolecis'' is a genus of lichen-forming fungi in the family Catillariaceae. It has four species of saxicolous (rock-dwelling) and crustose lichens. The genus was circumscribed by Italian botanist Vittore Benedetto Antonio Trevisan de Saint- ...

'' *''

Placolecis opaca ''Placolecis'' is a genus of lichen-forming fungi in the family Catillariaceae. It has four species of saxicolous (rock-dwelling) and crustose lichens. The genus was circumscribed by Italian botanist Vittore Benedetto Antonio Trevisan de Saint- ...

'' *''

Placolecis sublaevis ''Placolecis'' is a genus of lichen-forming fungi in the family Catillariaceae. It has four species of saxicolous (rock-dwelling) and crustose lichens. The genus was circumscribed by Italian botanist Vittore Benedetto Antonio Trevisan de Saint- ...

'' – China The taxon once known as ''Placolecis plumbea'' is now considered

synonymous A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

with ''

Pectenia plumbea ''Degelia plumbea'' (also called blue felt lichen) is a species of grey to blue-black or brown foliose lichen in the genus ''Degelia''. It mostly grows on trees in undisturbed woodlands but occasionally on coastal rocks. It is found widely in Br ...

''.

References

Lecanorales Lecanorales genera Lichen genera Taxa described in 1857 Taxa named by Vittore Benedetto Antonio Trevisan de Saint-Léon {{Lecanorales-stub