Found in Sri Lanka, it was formally described as a new species in 2014 by lichenologists Gothamie Weerakoon, Robert Lücking and Helge Thorsten Lumbsch.

The type specimen was collected from the Maussakanda Tea Estate (Matale, Central Province) at an altitude of 1,074 m (3,524 ft).

The lichen, which has been recorded from several locations in the Central Province, grows in semi-exposed, disturbed areas at high elevations.

The specific epithet canescens refers to the grey-coloured cover of the thallus.

Leucodecton fissurinum is somewhat similar in morphology, but it has a yellowish thallus and narrower ascomata pores that conceal the disc.