''Astrothelium simplex'' 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 ...

, first described in 2016. It is found in the

Atlantic Forest The Atlantic Forest ( pt, Mata Atlântica) is a South American forest that extends along the Atlantic coast of Brazil from Rio Grande do Norte state in the northeast to Rio Grande do Sul state in the south and inland as far as Paraguay and th ...

of Brazil.

Taxonomy

''Astrothelium simplex'' was formally described as a new species by the lichenologists

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 ...

and Suzana Maria de Azevedo Martins in 2016. The type specimen was collected by the second author in

Caraá Caraá is a municipality in the state of Rio Grande do Sul, Brazil where Rio dos Sinos' river rises. It was originally part of the city Santo Antônio da Patrulha, emancipated on December 28, 1995. History First inhabitants of Caraá were the i ...

Rio Grande do Sul Rio Grande do Sul (, , ; "Great River of the South") is a Federative units of Brazil, state in the South Region, Brazil, southern region of Brazil. It is the Federative_units_of_Brazil#List, fifth-most-populous state and the List of Brazilian st ...

, Brazil, on 27 April 2009.

Description

The thallus of ''Astrothelium simplex'' is , , somewhat shiny, and continuous, covering areas up to 7 cm in diameter and approximately 0.3 mm thick. The thallus is olive-green in colour and does not have a , but it does induce

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

formation on the

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 ...

bark. The ascomata are (pear-shaped), measuring about 0.6–0.9 mm in diameter, typically aggregated in groups of 2–5, and mostly immersed in the bark tissue. The wall is and up to 80 μm thick. Ostioles are eccentric, fused, raised, and dark brown, and surrounded by an ochraceous zone. The does not contain oil globules.

Asci ASCI or Asci may refer to: * Advertising Standards Council of India * Asci, the plural of ascus, in fungal anatomy * Accelerated Strategic Computing Initiative * American Society for Clinical Investigation * Argus Sour Crude Index * Association of ...

contain eight each. 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 ...

, 3-septate, , measuring 56–63 by 15–19 μm, with pointed ends and diamond-shaped , and lack a gelatinous sheath. were not observed.

Chemistry

The thallus surface of ''Astrothelium simplex'' is UV−, and the medulla does not react to potassium hydroxide (K−). Thin-layer chromatography analysis detected no secondary metabolites in this lichen.

Habitat and distribution

This species is found on the smooth bark of trees in the

and at the time of its original publication was known to occur only in Brazil.

References

{{Taxonbar, from=Q95573612 Trypetheliaceae Lichen species Lichens described in 2016 Lichens of Brazil Taxa named by André Aptroot