Distribution of Living and Fossil Coral Barnacles (Cirripedia; Pyrgomatidae) in Japan.

Abstract

The distribution of living and fossil coral-inhabiting barnacles (family Pyrgomatidae) was investigated in Japan. Twenty eight species of living coral barnacles were found from southwest Japan, but 2 species, Cantellius acutus and C. sumbawae, which were reported by UTINOMI (1962) and OGAWA and MATSUZAKI (1990) respectively, were not among them. Seven species are new records for Japan: Cantellius arcuatus, C. sinensis, C. tredecimus, C. sp. aff. albus, C. sp. aff. maldiviensis, Creusia spinulosa, and Savignium sp. aff. orientale. The number of species of living corals decreases markedly from the Okinawa region towards the north; however, the number of species of coral barnacles does not decrease as quickly. Eight species of fossil coral barnacles were found in the Holocene Numa Formation of the Boso Peninsula, central Japan. The species composition of living corals in the south Kii Peninsula, west Japan, resembles that of the fossil corals in the Numa Formation; however, the species composition of living coral barnacles in the south Kii Peninsula is distinctly different from that of the fossil coral barnacles in the Numa Formation.