Upretia squamulosa

Upretia squamulosa is a species of saxicolous (rock-dwelling), squamulose (scaly) lichen in the family Teloschistaceae. It was identified as a new species in 2019 from specimens collected in the arid valley of the Jinsha River in Yunnan, China.

Taxonomy
The lichen was scientifically described as a new species in 2019 by Yan Yun Zhang and Li Song Wang. The species epithet refers to its (scaly) thallus. The type specimen of Upretia squamulosa was collected in Yunnan Province, China, specifically in Huize County, Zhehai Town, at an elevation of 1720 m.

The genus Upretia is a recent classification within the subfamily Caloplacoideae of the family Teloschistaceae. Molecular phylogenetics placed Upretia squamulosa in a clade close to Upretia. This genus, initially proposed on the basis of specimens collected from India, is closely related to the monotypic genus Ioplaca, found in high elevations in the Himalayas.

Description
Upretia squamulosa is characterised by its squamulose, thallus that ranges in colour from greyish green to brown. The are convex, sometimes resembling a bullet shape, with their apex often free from the. This species has apothecia, which are pale brown to brown in colour, and  ascospores. The thallus and apothecia contain gyrophoric and lecanoric acids, but no anthraquinones are found in the apothecia.

The thallus of Upretia squamulosa is saxicolous and squamulose, without an margin, and can grow up to 7 cm in diameter. The upper surface is non-, smooth, and without cracks. The hymenium of the apothecia is colourless and the is pale brown. The species does not form pycnidia.

Habitat and distribution
Upretia squamulosa thrives in arid environments, particularly on rocky, at elevations ranging from 1240 to 3160 m. It has been found exclusively in China's Yunnan Province. The species is adapted to the hot and dry climate of the Jinsha-jiang River valley, which is dominated by shrubs and hosts a variety of crustose and squamulose lichens.