Resurrection of Alebion difficile (van Beneden, 1892) (Copepoda: Siphonostomatoida: Caligidae) with notes on other species of Alebion Krøyer, 1863 collected from elasmobranchs off South Africa and an updated key of the adult females. Systematic Parasitology, 95(8–9), 881–891
DOI: 10.1007/s11230-018-9811-3