The Ictinus Blue (Jalmenus ictinus) is a butterfly of the Lycaenidae family. It is found in the Australian Capital Territory, New South Wales, Queensland and Victoria. The wingspan is about 30 mm. The larvae feed on a various Acacia species, including Acacia bidwillii, Acacia dealbata, Acacia decurrens, Acacia harpophylla, Acacia implexa, Acacia mearnsii, Acacia melanoxylon, Acacia pendula and Acacia rubida, as well as Heterodendrum diversifolium. The Caterpillars are attended by the ant species Iridomyrmex purpureus and Iridomyrmex spadius.