A taxonomic analysis of Jania (Corallinaceae, Rhodophyta) in south-eastern Australia

Abstract. The genus Jania J.V.Lamour. (Corallinaceae, Corallinophycidae, Rhodophyta) is represented by five species (one with two varieties) in south-eastern Australia. Descriptions and detailed morphoanatomical accounts of these taxa are provided, along with keys, information on distribution, nomenclature and habitat, and brief biogeographic comparisons within Australia. Relevant type material is illustrated in detail. A list of 79 morphoanatomical characters and character states used by previous authors (since 1928) to delimit or identify species of Jania was compiled. Of these, nine were useful for delimiting species occurring in south-eastern Australia. Most can be delimited using a single diagnostic character, but Jania pedunculata J.V.Lamour. is highly variable and is distinguished from J. crassa J.V.Lamour. by using several overlapping characters. Twelve additional names have been recorded for south-eastern Australia. The types of seven of these were examined during the present study or in recent publications. Types of five entities could not be examined, because type material had not been designated or was not available for examination or the name was not validly published. Information on misidentified specimens, heterotypic synonyms, rejected names and unverified records for the region is also provided.