The front wings are characterized by a yellowish-white ground color, with numerous dark grey markings and two brownish sharply toothed transverse lines.

They have a characteristic bulbous swelling on the thorax and move with a looping motion as usual in measuring worms.

The giant looper has two generations per year in southern Europe, flying from April to May and from July to August.

They are polyphagous, feeding mainly on field wormwood (Artemisia campestris), Sambucus sp., rose ( Rosa sp.

), blackberry (Rubus fruticosus), broom (Cytisus scoparius), Taraxacum sp., birch (Betula sp.