The generic name honours lichenologist Rebecca Yahr, who "very kindly returned to the type locality to collect further material of this new species".

[2] The lichen forms small, smooth, greenish rounded patches, typically usually 0.4–0.6 cm (0.16–0.24 in) in diameter, with a whitish prothallus.

The species is characterized by hyphophores that are made of a circle of triangular lobes; additionally, the lichen has masses of moniliform hyphae that make long cilia on their outer cells.

[2] The lack of ascocarps means that the generic placement of this species cannot be made with certainty, but the authors chose Gyalectidium because of the similarity of its hyphophores with other members of that genus, and because of the intermingling of algae with the moniliform hyphae.

A year later, in their world monograph of Gyalectidium, Ferraro and colleagues proposed the monotypic section Goniolectidium and series Yahriae to contain the species.