Thioploca are sulphur oxidizing-nitrate reducing gliding filamentous benthic bacteria belonging to the Beggiatoaceae. In this paper we report on the discovery of Thioploca resulting from a commercial fishery survey of Trachurus capensis (horse mackerel) and Merluccius capensis (hake) carried out off Namibia between 18°00·1′S and 25°00·8′S from 4–10 December 1996, on board the RV ‘Welwitschia’. The first positive finding of sheathed, presumably vacuolated, Thioploca in the Benguela Current ecosystem is now reported.