The Search for Parasites of White Grubs (Melolonthids) in Zanzibar, Algeria, Morocco and France

Abstract

(1) An extensive survey covering a period of 18 months was carried out in Zanzibar, Algeria, Morocco and some parts of France with a view to obtaining parasites of white grubs for furthering the control of Phytalus smithi, Arrow, in Mauritius.(2) In Zanzibar the results of the survey showed that white grubs are of no great economic importance in clove plantations in this Island. Larvae of several species of white grubs were obtained, viz.: Entyposis impressa, Kolbe, Schizonycha spp., Anomala delagoa, Pèr., etc. ; these larvae are parasitised by the Dexiid fly, Microphthalma disjunctum, Wied. The percentage of parasitism at the time of the survey was from 0·10 to 0·53 per cent. Scoliids were not in great number ; the parasitism amounted to 0·6 per cent. Parasites of adult beetles were obtained on the following insects: Entyposis impressa, Kolbe, Schizonycha spp. and Anomala plebejus, Ol., the parasites being Pexopsis pyrrhaspis, Villen., and an Adapsilia, not yet determined. The parasitism on the above mentioned beetles varied from 1 to 9·7 per cent.