Metaphase chromosomes of parasitic wasp, Diachasmimorpha longicaudata (Hymenoptera: Braconidae) in Thailand

Abstract

Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a larval endoparasitoid of the fruit fly, Bactrocera correcta (Diptera: Tephritidae) that is important in biological control. We have analysed the metaphase chromosomes of this parasitoid using simple air-drying and squashed air-drying techniques. We examined the karyotypes of reproductive organs of pre-emerged adults and the cerebral ganglia of prepupae. Both show that females are diploid with a chromosome number of (2n)=40, whereas males are haploid with chromosome number of (n)=20. The haploid metaphase karyotype of D. longicaudata comprises 5 metacentric, 13 submetacentric and 2 subtelocentric chromosomes. We could not distinguish the sex chromosomes. These findings are the first record of the metaphase karyotype of this endoparasitoid.