イグサ
The larvae feed on the seeds of jointed rush ("Juncus articulatus"), soft rush ("Juncus effusus"), "Juncus inflexus", blunt-flowered rush ("Juncus subnodulosus"), sharp-flowered rush ("Juncus acutiflorus") and compact rush ("Juncus conglomeratus"). They form a case 5 mm long with an angle of 20°.