Tetraclita
Tetraclita is a genus of barnacles in the family Tetraclitidae. It includes several species that are found throughout the world’s oceans, primarily in intertidal zones.
Common Names
Species within the genus Tetraclita are often referred to as "rock barnacles" or "stalkless barnacles" due to their characteristic sessile, conical shape and lack of a stalk.
Characteristics
Members of the genus Tetraclita exhibit the following features:
- Conical, sessile body: They are firmly attached to rocky surfaces, lacking the flexible stalk found in other barnacle species.
- Four plates: Their shell (or carapace) is composed of four overlapping plates, hence the genus name "Tetraclita" (from the Greek words "tetra" meaning four and "klita" meaning "sloping").
- Filter feeders: They obtain food by filtering small organisms and particles from the surrounding water using their feathery appendages called cirri.
- Dioecious reproduction: Individuals are either male or female, and fertilization occurs externally.
- Larval stage: Tetraclita barnacles have a planktonic larval stage called a nauplius, which drifts in the water column before settling on a suitable substrate.
Environments
Tetraclita species are commonly found in intertidal zones, where they are exposed to the air during low tide and submerged during high tide. They are typically found attached to rocks, boulders, and other hard surfaces. Some species may also occur in the subtidal zone.
References
For more information about Tetraclita, you can consult the following sources: