Austrolittorina unifasciata, common name the banded periwinkle, is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles. It is also known as the blue periwinkle. Description The shell size varies between and . Distribution This species is the only one of its genus found in Australia. It is distributed in the Coral Sea off Queensland, Australia and in the Indian Ocean off Western Australia. This common periwinkle also lives on the rocky shore of New Zealand. It is also commonly found in South Pacific Islands such as Norfolk Island. Ecology This species of periwinkle lives in the splash zone and high intertidal zone, where it is found in clusters of individuals. The banded periwinkle grazes on lichen and algae. This small snail is eaten by crabs and birds. References Gray, J.E. 1826. Mollusca. pp. 474–496 in King, P.P. (ed.). Narrative of a Survey of the Intertropical and Western Coasts of Australia. Performed between the years 1818 and 1822; with Appendix B. London : John Murray Vol. 2 viii 637 pp., 9 pls Quoy, J.R.C. & Gaimard, J.P. 1833. Voyage de découvertes de l'Astrolabe, exécuté par ordre du Roi, pendant les années 1826–1829. Paris : J. Tastu Zoologie Vol. 2 pp. 321–686. Menke, C.T. 1843. Molluscorum Novae Hollandiae Specimen in Libraria Aulica Hahniana. Hannoverae : Libraria Aulica Hahniana pp. 1–46. Philippi, R.A. 1847. Abbildungen und Beschreibungen neuer oder wenig gekannter Conchylien. Cassel : Theodor Fischer Vol. 2 pp. 153–232 Gray, M.E. 1850. Figures of molluscous animals, selected from various authors. London : Longmans, Brown & Green Vol. 4 124 pp Nevill, G. 1885. Hand List of Mollusca in the Indian Museum, Calcutta. Part 2. Gastropoda. Calcutta : Government Printer pp. 1–306 Allan, J.K. 1950. Australian Shells: with related animals living in the sea, in freshwater and on the land. Melbourne : Georgian House xix, 470 pp., 45 pls, 112 text figs. W.J. Dakin – Australian Sea Shores; Angus and Robertson Publishers (1952) Iredale, T. & McMichael, D.F. 1962. A reference list of the marine Mollusca of New South Wales. Memoirs of the Australian Museum 11: 1–109 Macpherson, J.H. & Gabriel, C.J. 1962. Marine Molluscs of Victoria. Melbourne : Melbourne University Press & National Museum of Victoria 475 pp. Rosewater, J. 1970. The family Littorinidae in the Indo-Pacific. Part I. The subfamily Littorininae. Indo-Pacific Mollusca 2(11): 417–506 Branch, G.M. & Branch, M.L. 1981. Experimental