none The parasitoid Microctonus aethiopoides Loan (Hymenoptera: Braconidae) was introduced to New Zealand in 1982 for control of Sitona weevil, Sitona discoideus Gyllenhal (Coleoptera: Circulionidae), a pest of lucerne. Unfortunately, New Zealand populations of M. aethiopoides do not parasitise clover root weevil, Sitona lepidus Gyllenhal, but European populations do. Several PCR-based methods have demonstrated the existence of genetic variation between and amongst European and New Zealand populations of M. aethiopoides. However, enzyme electrophoresis methods have the potential to provide less expensive population markers, and these could also prove more useful than PCR-based markers for studying gene flow between European and New Zealand M. aethiopoides populations. This paper reports a preliminary assessment of allozyme variation between European and New Zealand M. aethiopoides. Nine enzymes and general proteins were assayed, but the only variation was observed at esterase (EST) with two alleles present at each of two loci. Biochemistry; Proteins; Genetics; Evolution; Variation; Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Insect hosts; Land zones; Australasian region; Palaearctic region; Eurasia; Australasia Sitona lepidus (Curculionidae); Hymenopteran parasites; Microctonus aethiopoides; Genetic differentiation between European & New Zealand parasite populations Microctonus aethiopoides (Braconidae); Enzymes; Population genetics; Biochemical variation; Allozyme variation; Coleopteran hosts; Sitona lepidus; Genetic differentiation between European & New Zealand parasite populations; Europe; Populations genetic differentiation from New Zealand populations; New Zealand; Populations genetic differentiation from European populations