Ferdinand Theissen

Ferdinand Theissen (27 July 1877 in Krefeld – 5 September 1919) was a German-Austrian Jesuit priest and mycologist.

He studied theology at the seminary in Feldkirch,[1] then from 1902 to 1908 was stationed in São Leopoldo, Brazil.

He died in September 1919 as a result of a climbing accident during a collection excursion in the Vorarlberg Alps.

[2] He was the author or co-author of numerous mycological taxa; with Hans Sydow he co-described the families Botryosphaeriaceae, Dothioraceae, Phyllachoraceae and Polystomellaceae.

[3][4][5][6] The genus Theissenia was named after him by André Maublanc (1914).