Xanthoparmelia scabrosa

Xanthoparmelia scabrosa, commonly known as the sexy footpath lichen or sexy pavement lichen, is a foliose lichen belonging to the family Parmeliaceae. It is highly adaptable and can grow on various substrates such as rock, tree bark, roofing tiles, glass, and in wetter regions, bitumen paths and roads. The lichen was first described by botanist Thomas Taylor in 1847 under the name *Parmelia scabrosa*. The type specimen was collected by James Drummond near Swan River in Western Australia. In 1974, it was reclassified as a species of *Xanthoparmelia* when Mason Hale elevated the subgenus to genus status. The nickname "sexy footpath lichen" was coined by Allison Knight during a talk for the Auckland Botanical Society and popularized by Peter de Lange as "sexy pavement lichen." The thallus of *Xanthoparmelia scabrosa* is leafy in appearance, with a yellow-green upper surface and a pale to dark brown lower surface. It is widely distributed across Australia and New Zealand and can also be found on Norfolk Island, Papua New Guinea, Fiji, Argentina, South Africa, and Japan. Notably, it thrives in environments like roads and footpaths, which are typically inhospitable to lichens. This lichen has the ability to tolerate high levels of heavy metals by accumulating them in its thallus, along with calcium. These traits make it a potential candidate for phytoremediation. Despite its resilience, *Xanthoparmelia scabrosa* has been marketed as a treatment for erectile dysfunction due to its PDE5 inhibitor content. However, scientists caution against this use, citing the potential toxicity of both ...