Practical techniques and accuracy for sexing the potato tuberworm, phthorimaea operculella (Lepidoptera: Gelechiidae)

Abstract

Sexual dimorphism between P. operculella females and males is evident in the pupal and adult stage. Male pupae are slightly smaller than female pupae and have a suture located further away from the end of the abdomen. The "scar"/ "width" (pupae) and "wings"/ "genitalia" (adults) methods are not entirely consistent. The "width" and the "wings" methods give a lower ratio than the "scar" and "genitalia" method, therefore overestimating the male/female ratio.