Suborder BALANOMORPHA Pilsbry, 1916

Symetrica Operculata tribe Symetrica Gruvel, 1905: 189.

Balanomorpha Pilsbry, 1916: 47 ( Balanidae sensu Darwin, 1854).

Diagnosis.

Peduncle absent; shells bilaterally symmetrical on either side of rostrocarinal axis; shell with parietal plates of carina, rostrum and one to three pairs of lateral plates, all separate from one another, variously fused or totally concrescent; base membranous or calcareous; hermaphroditic or with dwarf males.