A new family based on Illebdella papuensis gen. et sp. nov. is described. Characters include: body strongly depressed and wide; monostichodont, trignathous; pharynx euthylaematous with single secondary ridges in the dorsolateral positions; epididymis, a globular mass at xi/xii; no sperm ducts or ejaculatory bulbs; median regions, bimyomeric; vagina, caecate; no vaginal duct; ix to xxiv, 5-annulate; xxv, 4-annulate; xxvi, 3-annulate. Pattern, topographic, a wide median band of alternating maculae; a lateral catenulate row of large ovals. Hirudo catenulata Johansson 1918 is transferred to the new family and provisionally to the g. Illebdella.