[1] It was first identified and formally described by Evgeny Davydov and Lidia Yakovchenko in 2014, with the type specimen collected in the Altai Mountains.

Characteristics of the lichen include its distinct yellow thallus with greenish patches and a unique reproductive feature of producing a single spore per ascus.

The specific epithet smaragdulum refers to the emerald-like green patches observed on the thallus.

[2] Rhizocarpon smaragdulum has a yellow thallus that contains rhizocarpic acid and has an areolate to somewhat squamulose (scaly) surface.

[2] Rhizocarpon smaragdulum is primarily found in the Altai Mountains, growing in alpine environments above the tree line, typically on siliceous rocks in wet conditions.