Plumbagin and 7-methyljuglone are characteristic acetogenic (= derived from acetic acid) naphthoquinones (see Scheme 1) that allow a chemotaxonomic delimitation and the distinction between sundew (Drosera L.) species or species groups. This has recently been applied to several Australian species in Drosera sections Arachnopus Planch. (the 'D. indica L. complex') and Coelophylla Planch. (D. glanduligera Lehm.). By extending these studies to further accessions and species, some new and interesting insights into the chemical diversity of the genus were gained. In addition, the characteristic leaf and stem emergences of all examined Arachnopus species are featured in detail by microscopy images.