Taxonomical and biological information of the ectoparasitoid, Chlorocytus spicatus (Walker) (Hymenoptera: Pteromalidae), introduced to Korea with the cabbage seedpod weevil on rapeseed

Abstract

Chlorocytus spicatus (Walker) (Hymenoptera: Pteromalidae) is first confirmed as a larval ectoparasitoid of the cabbage seedpod weevil (CSPW), Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), on rapeseed (Brassica napus L., Brassicaceae) in Korea. The parasitism of this ectoparasitoid for the larvae of CSPW maximally was shown to be 12.5% on May 24 in Suncheon, Jeonnam Province, and 12.82% on June 12 in Andong, Gyeongbuk Province, when the damage rates of pods by the CSPW exceeded 30%, respectively. The pupal period of this ectoparasitoid was about 7 days and 6 days in females and males, respectively; the females had a life span of about 11 days; and the sex ratio was more than 4 females to 1 male. To aid their identification, we provide a detailed description supplemented by the scanning electron microphotographs of external structures and also present several biological data of its ectoparasitoid.

Keywords

• Ceutorhynchus obstrictus
• Chlorocytus spicatus
• Larval ectoparasitoid
• Pteromalidae
• Rapeseed