Astrothelium macroeustomum is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. Found in French Guiana, it was formally described as a new species in 2019 by lichenologists André Aptroot and Harrie Sipman. The type specimen was collected by Sipman from the Piste Crique Limonade at an altitude of 300 m (980 ft). The lichen has a mostly smooth, pale ochraceous-brown thallus that is somewhat shiny and covers areas up to 9 cm (4 in) in diameter. It is surrounded by a dark brown prothallus. It has pear-shaped (pyriform) ascomata, measuring 0.6–1.0 mm in diameter, which mostly aggregate in groups of two to five, and are more or less immersed in the tissue of the bark, below the thallus surface. They have convex, black ostioles (pores) that are surrounded by a yellowish-white ring of pruina. The ascospores are hyaline, spindle-shaped (fusiform) with five septa and measure 50–55 by 12–17 μm. The lichen contains lichexanthone, a lichen product that causes the ostioles of the ascomata to fluoresce yellow when lit with a long-wavelength UV light. The specific epithet macroeustomum refers to both its large spores and its similarity to Astrothelium eustomum.
Astrothelium elixii is a rare species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. It is found in the Beni Biological Station Biosphere Reserve in Bolivia.
Astrothelium sanguineoxanthum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Brazil, it was formally described as a new species in 2016 by Dutch lichenologist André Aptroot. The type specimen was collected in 1894 by Swedish botanist Gustaf Oskar Andersson Malme in Santa Anna da Chapada ; there, it was found in a rainforest growing on smooth tree bark. The lichen has a smooth, green to greyish thallus with whitish pseudostromata that range in shape from rounded to irregular to elongated. The thallus contains the lichen products isohypocrellin and lichexanthone; the latter substance causes the thallus and pseudostroma to fluoresce yellow when lit with a long-wavelength UV light, while the pigment isohypocrellin causes a K+ (green) chemical spot test reaction. The combination of characteristics of the lichen that distinguish it from others in Astrothelium are its ascospores, which turn violet in iodine potassium iodide (IKI) stain; and the arrangement and form of its ascomata, which are solitary to irregularly confluent, erumpent to prominent, and are whitish around the ostioles.
Astrothelium eumultiseptatum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Brazil, it was formally described as a new species in 2016 by lichenologists André Aptroot and Marcela Cáceres. The type specimen was collected by the authors in the Fazenda São Francisco, in a low-altitude primary rainforest. The lichen has a smooth and somewhat shiny, pale yellowish-grey thallus with a black prothallus line and covers areas of up to 7 cm (2.8 in) in diameter. The ascomata are pear-shaped (pyriform) and typically aggregate in groups of two to five, usually immersed in the bark tissue as pseudostromata. The ostioles of the ascomata contains lichexanthone, a lichen product that causes these structures to glow yellow when lit with a long-wavelength UV light. The main characteristic that distinguishes it from other members of Astrothelium are its ascospores, which measure 65–70 by 15–17 μm, and only have transverse septa.
Astrothelium eustomurale is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Brazil, it was formally described as a new species in 2016 by lichenologists André Aptroot and Marcela Cáceres. The type specimen was collected by the authors in the Parque Natural Municipal de Porto Velho, in a low-altitude primary rainforest. The lichen has a smooth and somewhat shiny, pale yellowish-grey thallus that lacks a prothallus and covers areas of up to 12 cm (4.7 in) in diameter. The presence of the lichen does not induce the formation of galls in the host. The ascomata are pear-shaped (pyriform) and typically occur in aggregates of two to five, usually immersed in the bark tissue under the pseudostromata and with a whitish-coloured tissue that contrasts with the surrounding thallus. Black pycnidia are abundant on the pseudostromata. The area around and including the ostiole of the ascomata contains lichexanthone, a lichen product that causes these areas to glow yellow when lit with a long-wavelength UV light. The characteristics that distinguish it from other members of Astrothelium include the UV+ yellow nature of the ostiole; and the fused, erumpent pseudostromatic ascomata that have a white cover contrasting it with the thallus colour.
Architrypethelium hyalinum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Costa Rica and Brazil, it was formally described as a new species in 2008 by lichenologist André Aptroot. The type specimen was collected by Harrie Sipman from the Las Cruces Biological Station in Puntarenas. The lichen has a smooth to uneven, olive-green thallus. Its ascomata occur solitarily, have an apical ostiole, and measure 0.7–1.5 mm in diameter. Ascospores number 4 to 8 per ascus, have an oblong to ellipsoid shape with 3 septa, and measure 100–150 by 30–50 μm. These spores are among the largest of the 3-septate lichens in the Trypetheliaceae. Both the thallus and ascomata contain lichexanthone, a lichen product that causes these structures to glow yellow when lit with a long-wavelength UV light; A. hyalinum is the only species in genus Architrypethelium that contains lichexanthone.
Astrothelium sinuosum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Brazil, it was formally described as a new species in 2016 by André Aptroot and Emerson Gumboski. The type specimen was collected by the second author from the Rio Pardinho e Rio Vermelho Environmental Protection Area ; there, in an Atlantic Forest habitat, it was found growing on smooth tree bark.
Astrothelium novemseptatum is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. It was first identified in Brazil, and has since been found in Guyana and Colombia. The lichen is characterized by its corticate, smooth, and somewhat shiny thallus, as well as its pyriform ascomata.
Astrothelium ochroleucoides is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. It is found in Brazil and Guyana.
Astrothelium testudineum is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. It is found in Brazil.
Astrothelium xanthosuperbum is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. It is found in Rondônia, Brazil. The species is characterized by its large muriform ascospores and is similar in appearance to Astrothelium disjunctum.
Viridothelium leptoseptatum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae, first described in 2016. Found in Brazil, it resembles Astrothelium aeneum but differs in several key aspects, including the absence of pigment on the thallus and specific features of its ascospores.
Astrothelium trematum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae, first described in 2018. Found only in Brazil, it is characterised by its lack of lichexanthone and pigments, and distinctive ascospores.
Astrothelium rhinothallinum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae, first described in 2018. It is found in Brazil.
Polymeridium longiflavens is a species of corticolous (bark-dwelling) crustose lichen in the family Trypetheliaceae, first described in 2016. It is found in Brazil.
Astrothelium rubrocrystallinum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae, first described in 2016. It is found in Brazil.
Astrothelium megeustomum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae, first scientifically described in 2016. It is found in Brazil.
Astrothelium macrostomum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. It is found in Brazil, Guyana, and Venezuela.
Astrothelium longisporum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. It occurs in the Atlantic Forest of Brazil.
Astrothelium graphicum is a species of lichen in the family Trypetheliaceae. This lichen features an extended, reticulate pseudostroma that is lower than its slightly bullate thallus.
