A cytogenetic study of three parasitic wasp species (Hymenoptera, Chalcidoidea, Eulophidae, Trichogrammatidae) from Brazil using chromosome morphometrics and base-specific fluorochrome staining.

Chromosomes of three chalcid wasp species from Brazil, Delvare et LaSalle, 1993, Cherian et Margabandhu, 1942 (both belonging to the family Eulophidae) and Riley, 1879 (Trichogrammatidae), were studied using chromosome morphometrics and base-specific fluorochrome staining. The present study confirmed that these species respectively have 2n = 12, 14 and 10. Chromomycin A / 4', 6-diamidino-2-phenylindole (CMA/DAPI) staining revealed a single CMA-positive and DAPI-negative band within haploid karyotypes of both and . This CG-rich band clearly corresponds to the nucleolus organizing region (NOR). Moreover, analogous multiple telomeric bands found on all chromosomes of may also represent NORs. Certain features of karyotype evolution of the phylogenetic lineage comprising both Eulophidae and Trichogrammatidae are discussed. The results obtained during the present study demonstrate the importance of chromosome research on tropical parasitoids that remain poorly known in this respect.