Isotoma fluviatilis, the swamp isotome[2] or blue star creeper,[3] is a small herbaceous perennial plant in the family Campanulaceae, native to Australia.

[4] The plant flowers during the summer months between November and March producing a carpet of white-blue five-petalled star-shaped flowers that are ideal as groundcovers in garden beds, rockeries or between paving stones.

[3] I. fluviatilis prefers dappled sunlight or part shade and moist soil.

[5] The species was first formally described as Lobelia fluviatilis by the botanist Robert Brown in 1810 in the work Prodromus Florae Novae Hollandiae and later reclassified in the genus Isotoma by George Bentham in 1864 in Flora Australiensis.

Several synonyms exist for this species including; Laurentia fluviatilis, Enchysia gaudichaudii and Rapuntium fluviatile.