Thoracica
Quick Summary
Thoracica is a subclass of marine crustaceans, commonly known as barnacles. These animals are highly adapted for a sedentary life. As adults, they are typically covered in calcareous plates and attach themselves to surfaces like rocks, pilings, or even the bodies of larger sea creatures. They feed by trapping tiny food particles with feathery appendages called cirri, which are modified swimming legs.1
Most barnacles are simultaneous hermaphrodites, possessing both male and female reproductive organs. After a larval stage, which includes nauplii and a cypris larva, they undergo metamorphosis to become sessile adults. The order Thoracica includes both stalked barnacles, like the goose barnacle, and sessile acorn barnacles, such as those that foul ships and harbour structures.12
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crustaceanAnnotated classificationOrder ThoracicaSilurian to present; the true barnacles; most are nonparasitic; larvae are nauplii and cyprids; adult body typically contained within calcareous shell plates; about 800 species.Subclass TantulocaridaHolocene; eggs give rise to a tantulus larva with head shield and 6 pairs of thoracic limbs;…
Read MoreOrder ThoracicaSilurian to present; the true barnacles; most are nonparasitic; larvae are nauplii and cyprids; adult body typically contained within calcareous shell plates; about 800 species.Subclass TantulocaridaHolocene; eggs give rise to a tantulus larva with head shield and 6 pairs of thoracic limbs;…
Read More- cirripedeDiversity and distribution
…principal superorder, however, is the Thoracica. It includes the goose and acorn barnacles. Thoracicans range from 1 millimetre (0.04 inch) to more than 10 centimetres (4 inches) in diameter and from less than one to more than 500 grams (0.04 to 17.6 ounces).
Read More…principal superorder, however, is the Thoracica. It includes the goose and acorn barnacles. Thoracicans range from 1 millimetre (0.04 inch) to more than 10 centimetres (4 inches) in diameter and from less than one to more than 500 grams (0.04 to 17.6 ounces).
Read More - cirripedeAnnotated classification
Superorder Thoracica (barnacles)Cambrian to present; conspicuous calcareous exoskeleton; posterior cirri evenly distributed along trunk; inhabit virtually all marine environments, several primitive members in the deep sea; 1 mm to 2 cm in length, some larger. About 800 species, some of which parasitize sharks, polychaetes, or…
Read MoreSuperorder Thoracica (barnacles)Cambrian to present; conspicuous calcareous exoskeleton; posterior cirri evenly distributed along trunk; inhabit virtually all marine environments, several primitive members in the deep sea; 1 mm to 2 cm in length, some larger. About 800 species, some of which parasitize sharks, polychaetes, or…
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