A new olenid trilobite species, Peltura undulata n. sp., is described from the Furongian (upper Cambrian) Parabolina lobata Zone, Peltura Superzone, of the Scandinavian Alum Shale Formation (Cambrian provisional Stage 10). The new species is recorded from the Oslo Region, southern Norway, Vastergotland and bland, south-central Sweden, as well as from ice-rafted boulders found in Germany. Like most other representatives of Peltura, the new taxon is characterised by pygidial features. It thus has a pygidium with three pairs of swellings along the posterolateral margin instead of spines, and the margin outline is undulating to some degree. In some cases the swellings are developed as broad-based semi-triangular projections. The new species, which is comparatively small, is restricted to the Pa. lobata Zone and accounts for up to 1 / 3 of the pelturid fauna, typically less. Remarks are given on the stratigraphic range of the co-occurring agnostoid Trilobagnostus holmi; it is inferred to be restricted to the Pa. lobata Zone.