''Astrothelium flavomaculatum'' 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

Trypetheliaceae The Trypetheliaceae are a family of mainly lichen-forming fungi in the order Trypetheliales. The family consists almost exclusively of corticolous (bark-dwelling), crustose lichens with an almost strictly tropical distribution. Taxonomy Trypethe ...

. Found in

Guyana Guyana, officially the Co-operative Republic of Guyana, is a country on the northern coast of South America, part of the historic British West Indies. entry "Guyana" Georgetown, Guyana, Georgetown is the capital of Guyana and is also the co ...

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

, and

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

, it 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 2016 by Dutch lichenologist

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 ...

. 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 by the author from the

Cordillera del Cóndor The Cordillera del Cóndor (Condor mountain range) is a mountain range in the eastern Andes that is shared by and part of the international border between Ecuador and Peru. The range extends approximately 150 km north to south and its m ...

(

Morona-Santiago Province Morona Santiago () is a province in Ecuador. The province was established on February 24, 1954. The capital is Macas. Economy The provincial economy is industrially unexploited to its potential due to poor means of transportation. Its economy ...

, Ecuador) at an altitude of . The lichen has a shiny, smooth to somewhat bullate (convex and swollen)

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 covers an area of up to in diameter. It is green with a thin orange

pruina Pruinescence , or pruinosity, is a "frosted" or dusty-looking coating on top of a surface. It may also be called a pruina (plural: ''pruinae''), from the Latin word for hoarfrost. The adjectival form is pruinose . Entomology In insects, a "bloom" ...

. 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 are

hyaline A hyaline substance is one with a glassy appearance. The word is derived from , and . Histopathology Hyaline cartilage is named after its glassy appearance on fresh gross pathology. On light microscopy of H&E stained slides, the extracellula ...

ellipsoid An ellipsoid is a surface that can be obtained from a sphere by deforming it by means of directional Scaling (geometry), scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a Surface (mathemat ...

in shape, and muriform (i.e. divided into internal chambers by transverse and longitudinal

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 ...

), with dimensions of 50–75 by 12–25

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 ...

. It is somewhat similar in appearance to '' Astrothelium graphicum '', but that species has somewhat smaller ascospores with lengths up to 66 μm.

References

flavomaculatum Lichen species Lichens described in 2016 Lichens of Ecuador Lichens of Guyana Lichens of Venezuela Taxa named by André Aptroot {{Dothideomycetes-stub