A new endoparasitic monogenean of Paradiplectanotrema Gerasev, Gayevskaya & Kovaleva, 1987, Paradiplectanotrema klimpeli sp. nov., is described from the southern Balinese coast, Indonesia. The new species is much larger, wider and characterized by the longest dorsal anchors compared with the congeners. Ventral anchors and ventral bars are the smallest in the genus, with a distinct ratio of 1:1. This is the first species with a gladiator breast-plate-shaped dorsal bar, with a length:width ratio of 1:1. Oesophagi of the Common Grinner Saurida tumbil (Bloch, 1795) (Synodontidae) were infected (prevalence = 17%) at an intensity of 12 (1–21). This is the first record of the genus from the eastern Indian Ocean, and lizardfishes represent a new host family. We provide light microscopy (in situ in oesophagal folds), three-dimensional confocal illustrations and a morphometric comparison of all congeners, with remarks on the recently described first Indonesian endoparasitic Monogenea Pseudempleurosoma haywardi Theisen, Palm, Al-Jufaili & Kleinertz, 2017. First 28S DNA sequences for Paradiplectanotrema allocate the new species close to endoparasitc freshwater monogeneans. Its ecology differs from Pseudempleurosoma Yamaguti, 1965 by utilizing deep-water fishes instead of coastal, coral reef-associated hosts; however, both are infecting schooling, bottom-dwelling fishes.