Related Research Articles
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmobile) and most are suspension feeders, but those in infraclass Rhizocephala are highly specialized parasites on crustaceans. They have four nektonic larval stages. Around 1,000 barnacle species are currently known. The name Cirripedia is Latin, meaning "curl-footed". The study of barnacles is called cirripedology.
Goose barnacles, also called stalked barnacles or gooseneck barnacles, are filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone. Goose barnacles formerly made up the taxonomic order Pedunculata, but research has resulted in the classification of stalked barnacles within multiple orders of the infraclass Thoracica.
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.
Rhizocephala are derived barnacles that parasitise mostly decapod crustaceans, but can also infest Peracarida, mantis shrimps and thoracican barnacles, and are found from the deep ocean to freshwater. Together with their sister groups Thoracica and Acrothoracica, they make up the subclass Cirripedia. Their body plan is uniquely reduced in an extreme adaptation to their parasitic lifestyle, and makes their relationship to other barnacles unrecognisable in the adult form. The name Rhizocephala derives from the Ancient Greek roots ῥίζα and κεφαλή, describing the adult female, which mostly consists of a network of thread-like extensions penetrating the body of the host.
Thecostraca is a class of marine invertebrates containing over 2,200 described species. Many species have planktonic larvae which become sessile or parasitic as adults.
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.
Sessilia is an unranked clade of barnacles, comprising the barnacles without stalks, or acorn barnacles. They form a monophyletic group and are probably derived from stalked or goose barnacles. Sessilia is divided into two orders. The Verrucomorpha contain two families, Verrucidae and Neoverrucidae, and the remaining 14 families are in the order Balanomorpha.
Ascothoracida is a small group of crustaceans, comprising around 100 species. They are found throughout the world, and are parasites on cnidarians and echinoderms.
The Acrothoracica are an infraclass of barnacles.
The Sacculinidae are a family of barnacles belonging to the bizarre parasitic and highly apomorphic infraclass Rhizocephala. The Sacculinidae is one of the two larger families of Rhizocephala, containing six genera:
The Peltogastridae are a family of barnacles belonging to the bizarre parasitic and highly apomorphic infraclass Rhizocephala. The Peltogastridae are by far the largest family of Rhizocephala. They comprise 14 genera, 3 of which were moved from the family Lernaeodiscidae.
In the past, Archaeobalanidae has been considered a family of barnacles of the order Sessilia. Research published in 2021 by Chan et al. resulted in the genera of Archaeobalanidae being merged with that of Balanidae, which now contains the members of both families. In the same work, Sessilia was not retained as an order of barnacles.
The biological systematics and taxonomy of invertebrates as proposed by Richard C. Brusca and Gary J. Brusca in 2003 is a system of classification of invertebrates, as a way to classify animals without backbones.
The clade Multicrustacea constitutes the largest superclass of crustaceans, containing approximately four-fifths of all described crustacean species, including crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, barnacles, copepods, amphipods, mantis shrimp and others. The largest branch of multicrustacea is the class Malacostraca.
Heterosaccus is a genus of barnacles in infraclass Rhizocephala. Like other taxa in this group, they parasitize crabs. Geoffroy Smith circumscribed the genus in 1906; he initially only included H. hians. Smith circumscribed a genus distinct from Sacculina due to a difference of the mesentery; in Heterosaccus, the mesentery does not stretch down to the mantle opening but rather only is present on the ring of attachment.
Clistosaccidae is a family of parasitic barnacles belonging to the bizarre and highly apomorphic infraclass Rhizocephala, which is part of the barnacle subclass Cirripedia.
Akentrogonida was formerly a suborder of barnacles belonging to the group Rhizocephala, now an infraclass. In research published by Chan et al. in 2021, the suborders Akentrogonida and Kentrogonida were removed from the infraclass Rhizocephala, leaving 13 families as children of Rhizocephala without intermediate orders or suborders.
Scalpellomorpha is an order of acorn barnacles in the class Thecostraca. There are about 11 families in 3 superfamilies and more than 450 described species in Scalpellomorpha.
Chthamalophilidae is a family of barnacles belonging to the infraclass Rhizocephala.
Duplorbidae is a family of barnacles belonging to the infraclass Rhizocephala.
References
- ↑ Chan, Benny K. K.; Dreyer, Niklas; Gale, Andy S.; Glenner, Henrik; et al. (2021). "The evolutionary diversity of barnacles, with an updated classification of fossil and living forms". Zoological Journal of the Linnean Society. 193 (3): 789–846. doi: 10.1093/zoolinnean/zlaa160 .
- ↑ "World Register of Marine Species, genus Kentrogonida" . Retrieved 2021-08-22.