Biological control of pestiferous slugs using Tetanocera elata (Fabricius) (Diptera: Sciomyzidae): Larval behavior and feeding on slugs exposed to Phasmarhabditis hermaphrodita (Schneider, 1859)

•T. elata larval survival outcomes depend on prey slug species.•Successful pupariation in T. elata is reduced for larvae fed on nematode-exposed slugs.•90% of T. elata neonate larvae without prey for four days pupariate successfully.•Neonate and third instar larvae appear to prioritise different predatory strategies.