The species exhibits two main forms: a bright green chloromorph with dichotomously branched lobes and brown fruiting bodies, and a dark blue-grey cyanomorph with phyllidia and white mottling.

It has a disjunct distribution across Atlantic Europe and Macaronesia, where it primarily grows as an epiphyte in laurisilva forests but can also be found on soil and rocks near water sources.

While historically confused with similar species worldwide, molecular studies have shown that true S. canariensis is restricted to western Europe and Macaronesia.

In his description, Delise distinguished S. canariensis from the similar species S. damicornis by its wider, divergent fronds that spread in a fan-like pattern rather than growing in bundled groups.

He noted its characteristic colour changes – displaying a vibrant green when humid, similar to the European S. pulmonacea (now Lobaria pulmonaria), and shifting to yellow-bronze when dry.

He described its distinctive features including deeply lacinated fronds with broad horn-like ends, smooth urn-shaped cyphellae with inflexed rims, and scattered red apothecia (fruiting bodies).

This led to the establishment of numerous infraspecific taxa within a broadly defined S. damicornis, with some authors even treating S. canariensis as a form or variety of that species.

[6] The underside of the thallus is a light to medium ochraceous-brown colour, featuring small pore-like structures (cyphellae) that blend in with the surrounding surface.