Hypogymnia imshaugii, commonly known as the forked tube lichen,[1] is a common species of foliose lichen in the family Parmeliaceae.

It was formally described as a new species by Norwegian botanist Hildur Krog in 1968.

[2] It has a grey to gray-green thallus with slender lobes measuring up to 2 mm wide that are branched dichotomously at regular intervals.

It has cup- to disc-shaped apothecia that are constricted at the base.

The lichen grows on conifer branches, preferring inland habitats that are moderately dry.