Xanthoria parietina, Whitehawk Hill. 18.01.22

Xanthoria parietina

X parietina is an extremely common species in Sussex; this specimen comes from a Hawthorne Tree on Whitehawk Hill; Hawthorne tress are normally covered in this species, especially those close to the sea.

General Description

A bright yellow to orange foliose lichen (often grey in the shade). Thallus of large slightly wrinkled overlapping lobes. Underside white. Fruiting bodies numerous especially towards the centre- orange apothecia with paler margin

Identification

Chemistry: K+ crimson/purple

Similar species: Xanthoria polycarpa has narrow lobes and numerous stalked apothecia which almost hide the thallus. X. aureola is coastal with narrow strap-like lobes. Caloplaca species are also K+ crimson/purple but are crustose.

See also Fungi of Great Britain and Ireland

Habitats

Urban, rural and coastal. On nutrient enriched trees (e.g. elder), rocks, walls and roofs, especially if exposed to bird droppings or air pollution.

Text by Heather Paul & Sue Knight British Lichen Society

Photo micrograms of an apothecum

10x image shows the whole apothecum

100x image with spores