Section Racemosae Research Articles

A monograph of Vaucheria (Vaucheriaceae, Chrysophyta) in south-eastern mainland Australia

Twenty-five species of Vaucheria have been found in south-eastern Australia, from both freshwater and saline habitats. As many collections were sterile, the study of plants in culture was necessary for identification as well as for the evaluation of taxonomic characters. A reassessment of the sectional classification has led to the raising of the subsections Racemosae (Walz) Heering and Sessiles (Walz) Heering to sectional level. Of the nine sections of the genus recognised, six are represented in south-eastern Australia. A key has been provided to all sections and species found during the study. Twentyone species are new records for the continent, including the newly described V. bicornigera [section Tubuligerae (Walz) Heering sens, nov.], V. gyrogyna [section Racemosae (Walz) sect, nov.] and V. nanandra [section Corniculatae (Walz) Heering sens. nov.]. Two other species, V. gardneri Collins and V. subarechavaletae Borge, were previously only known from the U.S.A. and Argentina respectively. The salient morphological features of all species have been illustrated with light micrographs or with scanning electron micrographs.