Balanus Temporal range: | |
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Balanus perforatus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Thecostraca |
Subclass: | Cirripedia |
(unranked): | Sessilia |
Order: | Balanomorpha |
Superfamily: | Balanoidea |
Family: | Balanidae |
Genus: | Balanus da Costa, 1778 |
Type species | |
Balanus balanus | |
Species | |
See text |
Balanus is a genus of barnacles in the family Balanidae of the subphylum Crustacea.
This genus is known in the fossil record from the Jurassic to the Quaternary periods (age range: from 189.6 to 0.0 million years ago.). Fossil shells within this genus have been found all over the world. [1]
The bodies of these organisms are totally enclosed by a stony gray-whitish shell. The size of these shells ranges from 5 millimeters to 10 centimeters. They take the form of a cone consisting of six plates fixed on the rocks. The active animal can only be observed within the water when the shell opens and the barnacles expose two branched appendages (cirri ) regularly hitting the water to catch food. They mainly feed on plankton.
These barnacles can be found in coastal areas at low shallow depth, although they can also be seen living out of the water. They commonly colonize stones, rocks and shells. They are found in abundance on the shells of mussels.
Species within the genus Balanus include: [2]
The species Balanus balanoides (common barnacle, common rock barnacle, northern rock barnacle) has been reclassified as Semibalanus balanoides in the family Archaeobalanidae, due to its membranous base.
Bulla is a genus of medium to large hermaphrodite sea snails, shelled marine opisthobranch gastropod molluscs. These herbivorous snails are in the suborder Cephalaspidea, headshield slugs, and the order Opisthobranchia.
Thoracica is an infraclass of crustaceans which contains the most familiar species of barnacles found on rocky coasts, such as Semibalanus balanoides and Chthamalus stellatus. They have six well-developed limbs, and may be either stalked or sessile. The carapace is heavily calcified. The group includes free-living and commensal species.
The Balanidae comprise a family of barnacles of the order Balanomorpha. As a result of research published in 2021 by Chan et al., the members of the family Archaeobalanidae were merged with this family.
Acorn barnacle and acorn shell are vernacular names for certain types of stalkless barnacles, generally excluding stalked or gooseneck barnacles. As adults they are typically cone-shaped, symmetrical, and attached to rocks or other fixed objects in the ocean. Members of the barnacle order Balanomorpha are often called acorn barnacles.
Semibalanus balanoides is a common and widespread boreo-arctic species of acorn barnacle. It is common on rocks and other substrates in the intertidal zone of north-western Europe and both coasts of North America.
Whale barnacles are species of acorn barnacle that belong to the family Coronulidae. They typically attach to baleen whales, and sometimes settle on toothed whales. The whale barnacles diverged from the turtle barnacles about three million years ago.
Megabalanus is a genus of barnacles in the family Balanidae. Members of the genus grow to 7 cm (2.8 in) in length and inhabit the lower intertidal zone.
Chthamalus is a genus of barnacles that is found along almost all non-boreal coasts of the northern hemisphere, as well as many regions in the southern hemisphere. These small barnacles have been studied in part because of the taxonomic confusion over a group of species that, by and large, are morphologically and ecologically quite similar. In recent years, molecular techniques have identified a number of cryptic species that have been subsequently confirmed by taxonomists using morphological measurements. Most recently the genus has been shown to be paraphyletic, with the genus Microeuraphia nested within Chthamalus.
Cerithium is a genus of small to medium-sized sea snails, marine gastropod molluscs in the family Cerithiidae, the ceriths.
Balanus nubilus, commonly called the giant acorn barnacle, is the world's largest barnacle, reaching a diameter of 15 cm (6 in) and a height of up to 30 cm (12 in), and containing the largest known muscle fibres.
Acasta is a genus of barnacles in the family Balanidae, containing the following species:
Amphibalanus improvisus, the bay barnacle, European acorn barnacle, is a species of acorn barnacle in the family Balanidae.
Megabalanus tintinnabulum is a species of large barnacle in the family Balanidae. It is the type species of the genus. The specific name comes from the Latin tintinnabulum meaning a handbell and probably refers to the fact that small groups of barnacles resemble clusters of miniature bells.
Fistulobalanus is a genus of barnacles, comprising the following species:
Amphibalanus is a genus of barnacle of the family Balanidae that includes species formerly assigned to Balanus. It contains the following species:
Concavus is a genus of barnacles.
Tetraclita is a genus of sessile barnacles in the family Tetraclitidae. There are more than 20 described species in Tetraclita.
Verruca is a genus of asymmetrical sessile barnacles in the family Verrucidae. There are about 20 described species in Verruca, around half of them extinct.
Notomegabalanus is a genus of acorn barnacles in the family Balanidae. There are about 12 described species in Notomegabalanus.