The authors describe a trap utilized in the field to catch possible intermediate hosts of Setaria labiatopapillosa attracted by naturally infected bovine. The trap was bulky and stable but also decomposable and removable. It was tested in an area of Friuli Venezia Giulia (Udine province, NE Italy) during 21 nights in the summer 1994 (29/6-29/9) and allowed to catch 16159 mosquitoes and 218 other Diptera, showing a very good efficiency.