Begrenzte Heterotrophie bei Amphidinium (Dinoflagellata)

An bakterienfreien Kulturen von Amphidinium höfleri in vollsynthetischem Nährmedium konnte mit dem Coulter-Counter gezeigt werden, daß gelöste Aminosäuren in Konzentrationen von 50 mg/l eine Erhöhung des Zellvolumens der Population um 6,1% bewirken. Eine Beeinflussung der Generationszeit konnte nicht festgestellt werden. Wurden die Aminosäuren in Konzentrationen von 200 µg/l, also in Konzentrationen, wie sie im Pelagial des Meeres vorkommen, geboten, so konnte keine Förderung des Wachstums nachgewiesen werden. With axenic cultures of Amphidinium höfleri it was shown by using the Coulter-Counter, that dissolved amino-acids in concentrations of 50 mg/l will increase the cellvolume by 6.1%. There was no effect on the generation time. If the aminoacids were added in concentrations of 200 µg/l - the concentration of natural sea water - then there was no effect

A Gordian knot: Nomenclature and taxonomy of Heterocapsa triquetra (Peridiniales: Heterocapsaceae)

In the course of polyphasic taxonomic work in the dinophytes, we became aware of a fundamental misapplication of the name Glenodinium triquetrum (now represented conceptually by a species of Kryptoperidinium), when Stein assigned it to Heterocapsa. Possible solutions involve a conflict between retaining Ehrenberg’s epithet in its correct application in the interest of priority and preserving current usage of Heterocapsa. However, we do not achieve a consensus on how to disentangle this Gordian knot, underlining that this is not a regular case of taxonomic confusion. We intend to stimulate a more general discussion about best practices in such cases, balancing between the interest of nomenclatural practicability and the respectful acknowledgement of scientific work, even if it was conducted many years ago

On the taxonomy of unarmored dinophytes (Dinophyta) from the Nrthwest African upwelling region

During "Meteor"-cruise no. 36, January/February 1975, in the Northwest African upwelling region (20° 30' to 22° 50' N, 16° 30' W to 18° 45' W) net samples of phytoplankton were analysed alive. A taxonomic study of 31 species of unarmored dinophytes belonging to the genera Amphidinium, Cochlodinium, Dissodinium, Erythropsidinium, Gymnodinium, Gyrodinium, Katodinium, Nematodinium, Noctiluca, Pronoctiluca, Protodinium, Pyrocystis, Torodinium, and Warnowia is provided. One species of each of the genera Cochlodinium, Gymnodinium, and Gyrodinium are described as new species. Changes and problems of nomenclature are discussed