Dirinaria applanata

Dirinaria applanata is a species of corticolous (bark-dwelling), foliose lichen in the family Caliciaceae. It has a wide distribution in tropical and subtropical areas of the world.

Taxonomy
The lichen was formally described as a new species, Parmelia applanata, by Antoine Laurent Apollinaire Fée in 1825. Dharani Dhar Awasthi transferred it to the Dirinaria in 1970.

Chemistry
Chemical analysis of Dirinaria applanata lead to the discovery of nine unique compounds. This includes a novel hopane derivative known as 1β-acetoxy-21α-hopane-3β,22-diol. Alongside this, researchers have identified six phenolic compounds: divaricatinic acid, methyl divaricatinate, methyl-β-orcinolcarboxylate, methyl haematommate, divarinol, and ramalinic acid A. Additionally, two xanthones, namely lichexanthone and 4,5-dichlorolichexanthone, were also isolated.

Species interactions
A fungus newly described in 2023, Cylindromonium dirinariae, was reported as a lichenicolous fungus with Dirinaria applanata as its host. This nectrioid fungus forms a pinkish colony with mainly solitary phialides producing ellipsoid, aseptate conidia in mucoid packets.