The genus Codium (Codiales, Chlorophyta) at Lord Howe Island (NSW).

Abstract

Five species of Codium have been found on the world's southernmost coral reef at Lord Howe Island, New South Wales (31°33'S.,159°03'E.). The genus forms, along with the brown algal order Dictyotales, a dominant marine algal group on the island. One species, the South African C. extricatum Silva, is a new record for the Australian region. Codium platydados is newly described based on Lord Howe, Great Barrier Reef and Philippine collections. Codium bulbopilum Setchell and C spongiosum Harvey have previously been recorded from the island and are major cover species in shallow lagoon waters. Codium arabicum is reported from the island and adjacent Australian mainland for the first time at what appear to be the species' southernmost limits of distribution. Anatomical variability and taxonomic relationships of the species are considered, and the geographical and local distributions discussed.