Members in this genus are superficially similar to the grass moths (Pyralidae: Crambinae), but these generally have some markings on the forewing, and have conspicuously long palpi. There are several species of leaf-rollers (Tortricidae) that are very similar, but have a pointed forewing apex and are smaller than Crambidia. C. impura is smaller than casta, and is light grey in colour, not white. Their ranges are currently not known to overlap in Alberta.