''Diorygma antillarum'' is a species of

corticolous This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found ...

(bark-dwelling),

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

in the family

Graphidaceae The Graphidaceae are a family of lichen-forming fungi in the order Graphidales. The family contains nearly a hundred genera and more than 2000 species. Although the family has a cosmopolitan distribution, most Graphidaceae species occur in tropic ...

. It is common and widespread in the

Neotropical realm The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...

, primarily found on trees in the shady

understory In forestry and ecology, understory (American English), or understorey (English in the Commonwealth of Nations, Commonwealth English), also known as underbrush or undergrowth, includes plant life growing beneath the Canopy (biology), forest ca ...

and in slightly illuminated habitats of lowland to

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is ...

rainforests. It produces

norstictic acid Norstictic acid is a depsidone produced as a secondary metabolites in lichens. The compound contains both an aldehyde carbonyl group and an adjacent hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical fo ...

and

salazinic acid Salazinic acid is a depsidone with a lactone ring. It is found in some lichens, and is especially prevalent in ''Parmotrema'' and '' Bulbothrix'', where its presence or absence is often used to help classify species in those genera. History In ...

Taxonomy

The lichen was first

formally described A species description is a formal scientific description of a newly encountered species, typically articulated through a scientific publication. Its purpose is to provide a clear description of a new species of organism and explain how it differ ...

as a new species in 1915 by the Finnish lichenologist

Edvard August Vainio Edvard August Vainio (born Edvard Lang; 5 August 185314 May 1929) was a Finnish lichenology, lichenologist. His early works on the lichens of Lapland (Finland), Lapland, his three-volume monograph on the lichen genus ''Cladonia'', and, in part ...

, who initially classified it in the genus '' Chiodecton''. The

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

was collected in 1803 by the American botanist

Stephen Elliott Stephen Elliott may refer to: Entertainment *Stephen Elliott (actor), (1918–2005), American actor * Stephen Elliott (author) (born 1971), American author and activist Sport * Steve Elliott (footballer, born 1958), English footballer * Steve Ell ...

from the Laudat Mountain in the

Lesser Antilles The Lesser Antilles is a group of islands in the Caribbean Sea, forming part of the West Indies in Caribbean, Caribbean region of the Americas. They are distinguished from the larger islands of the Greater Antilles to the west. They form an arc w ...

(now

Dominica Dominica, officially the Commonwealth of Dominica, is an island country in the Caribbean. It is part of the Windward Islands chain in the Lesser Antilles archipelago in the Caribbean Sea. The capital, Roseau, is located on the western side of t ...

) at an elevation of .

André Aptroot André Aptroot ( Heemskerk, 1961) is a Dutch mycologist and lichenologist. His primary research focus is on biodiversity, particularly tropical lichens, encompassing systematics, floristic surveys, and taxonomic reviews. A prolific research ...

Robert Lücking Robert Lücking (born 1964) is a German lichenologist, known for his extensive research on foliicolous lichens (lichens that live on leaves) and his significant contributions to the taxonomy, ecology, and biodiversity of fungi and lichens. He e ...

, and Göran Thor proposed a transfer to '' Herpothallon'' when they resurrected that genus in 2009. The genus ''Herpothallon'' typically includes

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 ...

- species with a thallus and

isidia An isidium (plural: isidia) is a tiny, wart- or finger-like outgrowth on the thallus surface of certain lichen species. It is one of two principal types of vegetative reproduction, vegetative reproductive structures in lichens, the other being ...

-like structures. These structures, while superficially resembling true isidia, lack and thus referred to as isidia-like. ''Herpothallon'' species are mostly sterile, with mature asci known from only a few taxa.

Molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

data has shown that ''H. antillarum'' does not align closely with the

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

of ''Herpothallon'' ('' H. rubrocinctum'') in the family

Arthoniaceae The Arthoniaceae are a family (biology), family of lichenized, Lichenicolous fungus, lichenicolous and saprobic fungi in the order Arthoniales. The Arthoniaceae is the largest family of Arthoniales, with around 800 species. Most species in Arthon ...

. Instead, ''H. antillarum'' is closely related to species within the genus ''Diorygma'' (

). The presence of a , fragile in ''H. antillarum'', a feature common in ''Diorygma'' species, along with its production of salazinic and

s, supports this reclassification. These chemical compounds are not typical for ''Herpothallon'' but are found in ''Diorygma''. Further phylogenetic analyses confirmed that ''H. antillarum'' belongs to the Graphidaceae, specifically within the subfamily Graphidoideae. For these reasons, Matthew Nelsen, Lücking, and Eimy Rivas Plata transferred the taxon to ''Diorygma'' in 2012.

References

{{Taxonbar, from=Q21268810 antillarum Lichen species Lichens described in 1915 Lichens of Central America Lichens of North America Lichens of South America Lichens of the Caribbean Taxa named by Edvard August Vainio