Survey of freshwater red algae (Rhodophyta) of south-eastern Australia

Abstract

A survey of rivers and other freshwater habitats in south-eastern Australia has resulted in the description and illustration of 14 species and two forms of red algae. With the exception of the two species of Nothocladus, all the taxa appear to be widespread in warm to cool temperate regions of the world. Three of the species [Chroodactylon ornatum (C.Ag.) Basson, Caloglossa leprieurii (Mont.) J.Ag. and Bostrychia scorpioides (Gmel.) Montagne] occur in brackish and marine habitats, as well as in fresh water. Two species [Hildenbrandia rivularis (Liebm.) J.Ag. and Audouinella hermannii Roth] are members of fundamentally marine genera that have one or a few distinct freshwater representatives. The remaining taxa belong to the genus Compsopogon (Compsopogonaceae, Erythropeltidales) and the family Batrachospermaceae (Nemaliales), which have no marine representatives and probably evolved in fresh water. This latter group consists of Compsopogon coeruleus (Balb.) Montagne, Batrachosperrnum atrum (Huds.) Harvey, B. ectocarpum Sirodot, B. Helminthoideum (Sirod.) Mori (two forms), B. keratophytum Bory, B. virgato-decaisneanum Sirodot, Sirodotia suecica Kylin (two forms), Nothocladus nodosus Skuja and N. lindaueri Skuja. The survey has added six new records to the Australian freshwater red algal flora. Nothocladus nodosus Skuja and N. tasmanicus Skuja are synonymized; N. lindaueri Skuja, previously recorded only from New Zealand, was found to be widely distributed in Victoria. Taxonomic characters in the genus Batrachospermum from Australia, the largest and most difficult group of species encountered, are reviewed.