Gryon gnidus, a scelionid egg-parasite ofAcanthomia tomentosicollis [Hem.: Coreidae] in Nigeria

Abstract

Gryon gnidusNixon (Hym.: Scelionidae) is an egg-parasite of the pigeon pea coreid,Acanthomia tomentosicollisStal in Nigeria. The life-cycle is completed in 8–14 days. The parasite is solitary and levels of parasitism in the field vary between 0% and 69%. The parasite is highly host-specific and eggs of other legume-infesting coreids includingAcanthomia horridaGerm.,Anoplocnemis curvipes F.,Mirpeurus torridusWestw., andRiptortus dentipes F. are not attacked. High levels of parasitism were recorded and parasite population build-up followed the trend of host population levels but did not prevent the host populations from reaching economic injury levels.