''Viridothelium ustulatum'' is a species of corticolous (bark-dwelling)

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Trypetheliaceae The Trypetheliaceae are a family of mainly lichen-forming fungi in the order Trypetheliales. Genera *'' Alloarthopyrenia'' – 1 sp. *''Aptrootia'' – 3 spp. *'' Architrypethelium'' – 8 spp. *''Astrothelium'' – ca. 275 spp. *'' Bathel ...

. Found in Brazil, it was formally described as a new species in 2017 by Marcela Eugenia da Silva Cáceres and

André Aptroot André Aptroot (Heemskerk, 1961) is a Dutch mycologist and lichenologist. In 1993 he did his PhD at the University of Utrecht under the supervision of Robbert Gradstein (nl). His dissertation was titled "Systematic studies on pyrenocarpous li ...

. The

type specimen In biology, a type is a particular wiktionary:en:specimen, 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 a ...

was collected by the authors along a trail near a

field station Field research, field studies, or fieldwork is the collection of raw data outside a laboratory, library, or workplace setting. The approaches and methods used in field research vary across disciplines. For example, biologists who conduct fie ...

in the

Adolfo Ducke Forest Reserve Amazon CIAT (5)

Adolfo Ducke Forest Reserve (Reserva Florestal Adol ...

(

Manaus Manaus () is the capital and largest city of the Brazilian state of Amazonas. It is the seventh-largest city in Brazil, with an estimated 2020 population of 2,219,580 distributed over a land area of about . Located at the east center of the s ...

); here it was found growing on tree bark in old-growth rainforest. The

thallus Thallus (plural: 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. Many of these organisms wer ...

of the lichen is dull olive-green, and lacks a prothallus. The species epithet refers to the black pseudostromata (a stroma in which fungal cells and remnants of

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

tissue are mixed).

Ascospore An ascus (; ) 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 genera or s ...

s number eight per

ascus An ascus (; ) 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 genera or s ...

, have three

septa The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people in five coun ...

, and measure 17–20 by 6.5–7.5

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

. ''Viridothelium ustulatum'' does not react to any of the standard chemical spot tests, and a chemical analysis with thin-layer chromatography did not find any secondary chemicals.

References

Trypetheliaceae Lichen species Lichens described in 2017 Lichens of North Brazil Taxa named by André Aptroot Taxa named by Marcela Cáceres {{Dothideomycetes-stub