Vermilacinia robusta is an olive-green fruticose lichen that occurs on rocks near ocean mist along the foggy Pacific Coast of southern California to northern Baja California and offshore islands.

[1] The epithet, robusta, was probably adopted in recognizing a more robust form of V. comboides, originally described as a variety of Ramalina combeoides by Reginald Heber Howe, Jr. in 1913.

Vermilainia robusta is classified in the subgenus Vermilacinia in which it is easily recognized by its relatively small number basal tubular branches, generally 5–10 in number, often inflated and connected to a basal holdfast.

Lichen substances are typical of the subgenus: T3, zeorin, and (-)-16 α-hydroxykaurane, occasionally with salazinic acid.

[4] to Niebla[5] The species was transferred to Vermilacinia when described in 1995, distinguished by its cortical morphology, lack of chondroid strands in the medulla, and by its lichen metabolites, notably (-)-16 α-hydroxykaurane.