Karl August Gustav Fiebrig-Gertz (25 May 1869, Hamburg – 25 October 1951, San Miguel de Tucumán) was a German-born Paraguayan botanist.
[3] In 1902 travelled to South America in order to collect botanical and entomological specimens for European museums.
[2] In 1934–36 he was director of the Paraguayan Department of Agriculture until leaving Paraguay following the Chaco War.
[4] In 1948 he returned to South America, where he worked as a botanist at the Instituto Miguel Lillo in Tucumán, Argentina.
[2][3] The plant genus Fiebrigiella (family Fabaceae) was named in his honor by Hermann Harms (1908).