Typification of Nitella gracilis (Sm.) C. Agardh var. confervacea Brébisson (= N. confervacea (Brébisson) A. Braun ex Leonhardi) with Remarks on Its Nomenclatural History

Abstract The correct name of the species of Nitella known as the ‘Least Stonewort’ has long been under debate. The problem has now been resolved as Nitella confervacea (Brebisson) A. Braun ex Leonhardi. This taxon, once thought to be an endemic of northwestern France, was neglected for a long time. The basionym Nitella gracilis var. confervacea Brebisson and other taxa connected to this name are typified, and their taxonomic status is assessed.