A catalogue with keys to the non-geniculate coralline algae (Corallinales, Rhodophyta) of South Africa

Abstract

Non-geniculate coralline red algae are common in all of the world’s oceans, where they often occupy close to 100% of the primary rocky substratum. The South African rocky subtidal and intertidal habitats in particular, are rich in diversity and abundance of non-geniculate coralline red algae. Despite their ubiquity, they are a poorly known and poorly understood group of marine organisms. Few scattered records of non-geniculate coralline red algae were published prior to 1993, but these should be treated with caution since many taxa have undergone major taxonomic review since then. Also, generic names such as Lithophyllum and Lithothamnion were loosely used by many authors for a host of different non-geniculate coralline algae. A series of taxonomic studies, based mainly on the Western Cape Province of South Africa, published particularly between 1993 and 2000, has significantly extended our knowledge of these algae from southern Africa. References to these latter papers and the older records are now gathered here and a list of the well delimited families (3), subfamilies (4), genera (17) and species (43) are presented. A catalogue with keys to the various taxonomic categories is also provided. A marked reduction in the number of real taxa has been found largely because many earlier recorded taxa have been reduced to synonymy, or have not been verified, or examined in a modern context and so their placement is considered dubious, particularly because the Corallinales have undergone major taxonomic revisions in recent years.