Verrucaria kowenensis is a species of terricolous (ground-dwelling), crustose lichen in the family Verrucariaceae. It is found in the Australian Capital Territory of Australia, where it grows on silica-rich soil.
The lichen was formally described as a new species in 2020 by lichenologist Patrick M. McCarthy. The type specimen was collected by the author from Kowen Forest (Australian Capital Territory) at an altitude of ; there, on an old road bank bordering dry Eucalyptus woodland, it was found growing on siliceous soil. The species name refers to the type locality. Other lichens occurring in this species-poor habitat include Trapelia concentrica and unidentified species of Sarcogyne and Arthonia.
Verrucaria kowenensis has an inconspicuous thallus with a pale grey-green or light to medium greenish-grey hue. Its thallus, which is to , is comparatively thick, , and primarily algal. The (fruiting bodies), though numerous, are extremely small and do not have an . They are largely submerged within the thallus, displaying a black apex, with the remaining colourless at the sides and base. Its , which have a arrangement in the ascus, measure between 11 and 20 üm in length and 5âÂÂ7.5 üm in width.
Verrucaria kowenensis shares a wide range of similarities with the land-dwelling Australian endemic species, V. solicola. However, it distinguishes itself by possessing a thallus that is thicker, areolate, or finely pseudosquamulose with a dual-layered cortex. Further, it has considerably smaller perithecia with a thinner and lighter exciple on the sides and at the base, and its asci are also shorter.