Pieter B. Pelser (born 12 January 1976) is a lecturer in Plant Systematics and the curator of the herbarium at the University of Canterbury in Christchurch, New Zealand. One research interest is the evolutionary history of the tribe Senecioneae, one of the largest tribes in the largest family of flowering plants.[1] He wrote the most recent attempt to define and delimit this tribe and its problematic founding species Senecio.[2] He also studies insects that eat these plants (Longitarsus) which contain pyrrolizidine alkaloids and what makes them choose which plants they eat.[3]