The barnacles are a taxon of marine crustaceans that comprises three major groups. Each of those groups represents a highly adapted taxon, with very specialized body plans and biological adaptions. These are the sessile barnacles (Thoracica), as the commonly known rock barnacles, the Rhizocephala, a group of parasites on other crustaceans, and the burrowing barnacles (Acrothoracica), which bore themselves into hard materials.

The sessile barnacles are key species in many marine benthic habitats, often dominating the fauna in the rocky intertidal. Their ability of mass settlement and rapid growth makes them one of the most important bio fouling organisms. Barnacles firmly attach themselves to hard surfaces, staying on the same spot for their whole life and filter the surrounding water for food. From their outer appearance, hardly recognizable as a Crustacea, the famous American zoologist from the 19th century, Louis Agassiz, describes them as “nothing more than a little shrimp-like animal, standing on its head in a limestone house and kicking food into its mouth”. While these sessile barnacles can already be seen as a very unusual group of crustaceans, the Rhizocephala, or parasitic barnacles, appear even more bizarre. Those parasites enter a crab or shrimp as tiny larvae. They grow an extensive root system inside the body of their host and eventually break through the shell of the crab to form a sac like outer organ, in which they breed the next generation. Sometimes these parasites are called body snatchers, since they take out all their energy from the crabs and even steer their behavior. The third barnacle group is the Acrothoracica, or burrowing barnacles. These are tiny animals of only a few millimeters. Instead of forming protective wall plates like the sessile barnacles, these animals burrow into hard substances, like empty snail shells, for protection.

While rock barnacle are a common sight for everyone spending time on the seashore, the species identification of these animals can be difficult and often is a challenge even to biologists. Apart from the frequently encountered species from the intertidal, a major part of barnacle fauna in Norway is unknown to the public, and a high number of undescribed species remains in the local fauna.

The aim of the present study therefore is to investigate the complete Cirripedia fauna in Norway, including the description of new species to science. By assembling a DNA barcode database of all local barnacle species, and providing an illustrative and user-friendly identification key combined with species information sheets, we will provide practical applicable methods for species identification, both for professional users and the general public. Mapping of the Cirripedia fauna will serve as a baseline study for changes in the distribution pattern of these species that can be expected in the next decades due to climate change. Further, the distribution range of invasive, non-native barnacle species will be monitored during the project.

Project leader: Christoph Noever, University of Bergen
Project period: May 2015 – December 2016

The species Peltogaster paguri on the heremit crab Pagurus bernhardus.

The species Lernaeodiscus ingolfi on rugose squat lobster (Pagurus bernhardus