Nederlandse Kranswieren 2. Boomglanswieren – Groot boomglanswier [Tolypella prolifera (Ziz ex A. Braun) Leonhardi]

A characteristic species of small ephemeric waters in the Dutch riverclay area is Tolypella prolifera. The distribution of this species is most likely restricted to Europe, with an optimal occurrence in the Netherlands. Due to the pollution of the river Rhine many localities of this species have disappeared. Data on distribution, taxonomy, ecology and phytosociology are presented and possibilities for the protection of this rare species in the Netherlands are discussed.