Northern Prairie Wildlife Research Center
Waxy white with broad lemon yellow banding. Head very pale with slightly differentiated snowflakelike spots; some stemmata black. First thoracic segment without yellow. Above level of spiracles: front two-thirds of each segment yellowed back to seventh abdominal segment; uniformly yellow from spiracles to above prolegs. Setae fine, inconspicuous. Caterpillar figured here may be that of the closely related pale mustard sallow, (P. citromba). Food: witchhazels. Caterpillar: May to June; 1 generation.