''Astrothelium flavomaculatum'' is a species of corticolous (bark-dwelling), crustose lichen in the family

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

Guyana Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...

, Venezuela, and Ecuador, it was formally described as a new species in 2016 by Dutch lichenologist

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 was collected by the author from the Cordillera del Cóndor ( Morona-Santiago Province, Ecuador) at an altitude of . The lichen has a shiny, smooth to somewhat bullate (convex and swollen) thallus that covers an area of up to in diameter. It is green with a thin orange pruina. Its ascospores are

hyaline A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none. Histopathology Hyaline cartilage is ...

ellipsoid An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...

in shape, and muriform (i.e. divided into internal chambers by transverse and longitudinal septa), with dimensions of 50–75 by 12–25

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 ...

. 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