 Morphological and molecular phylogenetic analyses suggest that "Negaprion" is grouped with the whitetip reef shark ("Triaenodon") and the sliteye shark ("Loxodon") in occupying an intermediate position on the carcharhinid evolutionary tree, between the most basal genera ("Galeocerdo", "Rhizoprionodon", and "Scoliodon") and the most derived ("Carcharhinus" and "Sphyrna").The range of the sicklefin lemon shark extends from South Africa to the Red Sea (including Mauritius, the Seychelles, and Madagascar), continuing eastward along the coast of the Indian subcontinent to Southeast Asia, extending as far north as Taiwan and the Philippines, and as far south as New Guinea and northern Australia.This species is also found around numerous Pacific islands, including New Caledonia, Palau, the Marshall Islands, the Solomon Islands, Fiji, Vanuatu, and French Polynesia.