Thoracica is a superorder 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.
This article follows Martin and Davis in placing Thoracica as a superorder of Cirripedia and in the following classification of thoracicans down to the level of families:
Superorder Thoracica Darwin, 1854
Order Pedunculata Lamarck, 1818Suborder Heteralepadomorpha Newman, 1987Anelasmatidae Gruvel, 1905Heteralepadidae Nilsson-Cantell, 1921Koleolepadidae Hiro, 1933Malacolepadidae Hiro, 1937Microlepadidae Zevina, 1980Rhizolepadidae Zevina, 1980Suborder Iblomorpha Newman, 1987Iblidae Leach, 1825Suborder Lepadomorpha Pilsbry, 1916Lepadidae Darwin, 1852Oxynaspididae Gruvel, 1905Poecilasmatidae Annandale, 1909Suborder Scalpellomorpha Newman, 1987Calanticidae Zevina, 1978Lithotryidae Gruvel, 1905Pollicipedidae Leach, 1817Scalpellidae Pilsbry, 1907Order Sessilia Lamarck, 1818Suborder Brachylepadomorpha Withers, 1923Neobrachylepadidae Newman & Yamaguchi, 1995Suborder Verrucomorpha Pilsbry, 1916Neoverrucidae Newman, 1989Verrucidae Darwin, 1854Suborder Balanomorpha Pilsbry, 1916Superfamily Chionelasmatoidea Buckeridge, 1983Chionelasmatidae Buckeridge, 1983Superfamily Pachylasmatoidea Utinomi, 1968Pachylasmatidae Utinomi, 1968Superfamily Chthamaloidea Darwin, 1854Catophragmidae Utinomi, 1968Chthamalidae Darwin, 1854Superfamily Coronuloidea Leach, 1817Chelonibiidae Pilsbry, 1916Coronulidae Leach, 1817Platylepadidae Newman & Ross, 1976Superfamily Tetraclitoidea Gruvel, 1903Bathylasmatidae Newman & Ross, 1971Tetraclitidae Gruvel, 1903Superfamily Balanoidea Leach, 1817Archaeobalanidae Newman & Ross, 1976Balanidae Leach, 1817Pyrgomatidae Gray, 1825
