The red hornweed is small and branched red algae that can grow about 30 cm long. It is widely found in the lower seashore and just below. It grows on rocks or on other larger algae.
The red hornweed is found all over the world, in the Southern Hemisphere, the Northern Hemisphere, in the Atlantic, Pacific and Indian Oceans. In fact, there are not many Icelandic organisms found so widely.