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2.2.7. Sub-class 7. Cirripedia
Unit 2 - Sub-phylum Crustacea
2.2.7. Sub-class 7. Cirripedia (Barnacles)
1. Marine crustaceans.
2. Adults sessile, parasitic or attached to rocks, piles, seaweeds, boats etc. by cement gland on first antenna.
3. Body relatively large and imperfectly segmented.
4. Carapace, made of two skin folds becomes mantle, surrounding body.
5. 6 pairs of biramous, cirriform thoracic appendages.
6. Abdomen rudimentary, limbless, ending in a pair of caudal styles.
7. Antennules become vestigial and modified for attachment.
8. Antennae and compound eyes disappear in the adult.
9. Monoecious; mostly hermaphroditic, development includes free-swimming nauplius which passes through a cypris stage, enclosed in a bivalve shell.
Eg. Lepas (Goose neck barnacle), Balanus (Acorn barnacle), Sacculina
Last modified: Tuesday, 2 August 2011, 10:37 AM