Sigara fallenoidea is a species of water boatman in the family Corixidae in the order Hemiptera. It was described by Hungerford and the type locality is in Canada. In Ireland Walton discovered a 'new' species of corixidae which he named Sigara pearcei.[1] This was synonymised by Hungerford in 1950. The distribution of S. fallenoidea is therefore an extraordinary one including Canada, Ireland, Norway, Finland, Sweden, Ukraine and Russia.[2] In Ireland, Sigara fallenoidea is found in all the large lakes on the island. There are confirmed records from Loughs Neagh, Beg and Portmore Lough; Upper and Lower Lough Erne; Lough Melvin; Loughs Ree, Derg and Key on the Shannon; and Lough Corrib.[3]