Balanus balanus
From Wikipedia, the free encyclopedia
| Balanus balanus | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Thecostraca |
| Subclass: | Cirripedia |
| Order: | Balanomorpha |
| Family: | Balanidae |
| Genus: | Balanus |
| Species: | B. balanus |
| Binomial name | |
| Balanus balanus | |
Balanus balanus is a species of acorn barnacle in the Balanidae family. It is native to the colder seas of the Northern Hemisphere.
Unlike most crustaceans, barnacles are unable to move from place to place. Cement glands near the base of the antennae fix them to the rock. The carapace of this species is conical with a circular base which has an irregular edge and a diameter of up to three centimeters. The surface is ridged and white or pale brown. The cover plates protecting the opening are shaped like the beak of a bird.[2]
Ecology
This species is found at depths of up to 150 metres (490 ft),[3] commonly between 20 -- 30 meters [4] and grows on bedrock, boulders, pebbles and shells.[5] It seems to favor habitats with strong currents and when overcrowding occurs, adopts different shapes to fit the space available. It is often found growing alongside another barnacle, Balanus crenatus. Other species often found in its vicinity include Tubularia larynx, Obelia geniculata, Pomatoceros triqueter, Pecten maximus, Hydroides norvegica, Chlamys opercularis and Sertularia species. Coralline algae was often present as were the whelk, the European edible sea urchin (Echinus esculentus), the great spider crab (Hyas araneus) and the shore crab (Carcinus maenas).[6]
The main predator is the juvenile common starfish (Asterias rubens). Medium sized barnacles seem to be at greatest risk. Small specimens are ignored while large specimens seem able to withstand attack.[7] Other predators are snails, worms and birds.[8]
