''Chrysothrix bergeri'' is a species of

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

Chrysotrichaceae Chrysotrichaceae is a family of lichenized fungi in the order Arthoniales. Member of this family have a widespread distribution, but are especially prevalent in tropical areas. "Chrysothrichaceae" and "Chrysothricaceae" are alternative spellings ...

. It is found in the southeastern United States and the Caribbean, where it grows as a bright yellow, powdery crust on the bark and wood of mostly hardwoods.

Taxonomy

''Chrysothrix bergeri'' was

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 2020 by Scott LaGreca.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 originally collected in 1922 from Confianza Estate in

Cuba Cuba, officially the Republic of Cuba, is an island country, comprising the island of Cuba (largest island), Isla de la Juventud, and List of islands of Cuba, 4,195 islands, islets and cays surrounding the main island. It is located where the ...

. Although it had previously been mentioned in the scientific literature as an undescribed species, it had not been formally named. The distribution of the lichen extends from the

southeastern United States The Southeastern United States, also known as the American Southeast or simply the Southeast, is a geographical List of regions in the United States, region of the United States located in the eastern portion of the Southern United States and t ...

, southwards to the

Bahamas The Bahamas, officially the Commonwealth of The Bahamas, is an archipelagic and island country within the Lucayan Archipelago of the Atlantic Ocean. It contains 97 per cent of the archipelago's land area and 88 per cent of its population. ...

and

, and eastwards to

Bermuda Bermuda is a British Overseas Territories, British Overseas Territory in the Atlantic Ocean, North Atlantic Ocean. The closest land outside the territory is in the American state of North Carolina, about to the west-northwest. Bermuda is an ...

. Although found mostly on hardwoods (usually

oak An oak is a hardwood tree or shrub in the genus ''Quercus'' of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisp ...

), other recorded substrates include ''

Casuarina equisetifolia ''Casuarina equisetifolia'', commonly known as coastal she-oak, horsetail she-oak, ironwood, beach sheoak, beach casuarina, whistling tree or Australian pine is a species of flowering plant in the family Casuarinaceae and is native to Australia, ...

'', ''

Prunus caroliniana ''Prunus caroliniana'', known as the Carolina laurelcherry, Carolina cherry laurel, Carolina cherry, or Cherry laurel, is a small evergreen flowering tree native to the lowlands of Southeastern United States, from North Carolina south to Florida ...

'', ''

Suriana maritima ''Suriana'' is a monotypic genus of flowering plants containing only ''Suriana maritima'', which is commonly known as bay cedar. Distribution It has a pantropical distribution and can be found on coasts in the New and Old World tropics. Native ...

'', ''

Juniperus Junipers are coniferous trees and shrubs in the genus ''Juniperus'' ( ) of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere as far south ...

'', ''

Pinus A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. ''World Flora Online'' accepts 134 species-rank taxa (119 species and 15 nothospecies) of pines as c ...

'', and ''

Taxodium ''Taxodium'' is a genus of one to three species (depending on taxonomic opinion) of extremely flood-tolerant conifers in the cypress family, Cupressaceae. The name is derived from the Latin word ''taxus'', meaning " yew", and the Greek word ' ...

''. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

''bergeri'' honours Franz Berger, an Austrian medical doctor and botanical collector, "and the first person to recognize this new taxon in Bermuda".

Description

The species has a bright yellow

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 ...

that is both crustose and leprose (powdery), and which grows on both the bark and wood of trees. The granules comprising the thallus are typically 20–45

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

in diameter. Its

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 number eight per

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 ...

and measure about 9–15 by 3–4 μm, with 3 transverse

septa SEPTA, the Southeastern Pennsylvania Transportation Authority, is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly four million people througho ...

. Two

chemotype A chemotype (sometimes chemovar) is a chemically distinct entity in a plant or microorganism, with differences in the composition of the secondary metabolites. Minor genetic and epigenetic changes with little or no effect on morphology or anatomy ...

s of this species have been identified. One contains calycin and pinastric acid as major

lichen product Lichen products, also known as lichen substances, are organic compounds produced by a lichen. Specifically, they are secondary metabolites. Lichen products are represented in several different chemical classes, including terpenoids, orcinol deri ...

s and leprapinic acid as a minor metabolite, while the other chemotype has only calycin.

References

{{Taxonbar, from= Q111633533 bergeri Lichen species Lichens described in 2020 Lichens of the Caribbean Lichens of the Southeastern United States Fungi without expected TNC conservation status Taxa named by Scott LaGreca