Species:

Note: The species is relatively uncommon in Norway, but has been recorded as far north as the county of Troms. It can be found growing epiphytically on the kelp Laminaria hyperborea. Thallus consists of prostrate axes bearing erect axes. Erect thalli have distinct main axes with up to 3-4 orders of side branches in an alternating pattern, all branches are in one plane. All axes are without cortex cells and have 7-8 pericentral cells in segments. Specimens may become up to 7 cm long, but normally relatively small individuals are found in Norway.