Description and Classification of Rhodoliths (Rhodoids, Rhodolites)

Abstract

Nodules composed of coralline algae have been described since the latter part of the eighteenth centuary (Pallas 1766, Ellis and Solander 1786). The first extensive descriptive work on free-living corallines was undertaken by Foslie (1894), Lemoine (1910) and later by Cabioch (1966, 1969). Bosellini and Ginsburg (1970) were the first to recognise the palaeoecological significance of rhodoliths and they suggested a descriptive terminology. They proposed the term rhodolite for “... nodules and detached branch growths with a nodular form composed principally of coralline algae ...”. Unfortunately the term rhodolite has priority for a variety of garnet (Binda 1973) and therefore “rhodolith” has now become the accepted term (Toomey 1975). More recently “rhodoid” has been suggested (Peryt, this vol.) but this is not preferred by the author because (a) an acceptable term is already in use and (b) its etymology is unsuitable (Rhodolith-rhodophycean or red stone, rhodoid-rhodophycean or red-like).