Sessilia is an unranked

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

barnacle Barnacles are arthropods of the subclass (taxonomy), subclass Cirripedia in the subphylum Crustacean, Crustacea. They are related to crabs and lobsters, with similar Nauplius (larva), nauplius larvae. Barnacles are exclusively marine invertebra ...

s, comprising the barnacles without stalks, or acorn barnacles. They form a

monophyletic group In biology, a clade (), also known as a monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy ...

and are probably derived from stalked or

goose barnacles Goose barnacles, also called percebes, turtle-claw barnacles, stalked barnacles, gooseneck barnacles, are filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone. Goose barnacles formerl ...

. Sessilia is divided into two orders. The

Verrucomorpha Verrucomorpha is an order of asymmetrical sessile barnacles in the class Thecostraca. They are typically found in deeper and deep-sea habitats. There are 2 families and more than 100 described species in Verrucomorpha. Families These families be ...

contain two families,

Verrucidae Verrucidae is a family of asymmetrical sessile barnacles in the order Verrucomorpha. There are about 14 genera and more than 90 described species in Verrucidae. Genera These genera belong to the family Verrucidae: * '' Altiverruca'' Pilsbry, 19 ...

and

Neoverrucidae Neoverrucidae is a family of crustaceans belonging to the order Scalpellomorpha Scalpellomorpha is an order of barnacles in the class Thecostraca. There are about 11 families in 3 superfamilies and more than 450 described species in Scalpellom ...

, and the remaining 14 families are in the order

Balanomorpha The Balanomorpha are an order of barnacles, containing familiar sessile shelled acorn barnacles of the seashore. The order contains these families: * Austrobalanidae Newman & Ross, 1976 * Balanidae Leach, 1817 (acorn barnacles) * Bathylasmatid ...

References

External links

* Barnacles Crustacean orders {{maxillopoda-stub da:Rur de:Seepocken pl:Pąkle