Two biotypes of the braconid parasitoid, M. aethiopoides Loan, were analyzed morphologically: a European biotype reared from the alfalfa weevil, Hypera postica (Gyllenhal), and a Moroccan biotype reared from clover root curculios, Sitona spp. European specimens were generally larger, darker and more setose, rugose and areolated than their Moroccan counteparts. Females of the 2 biotypes were identified easily by the number of articles in the antennal flagellum, number of segments in the labial palps, extent of mesonotal areolation, size and color. These characters, except color, also were useful in characterizing males, although character overlap generally was greater. A discriminant function based on 1 meristic and 6 linear characters aided identification of males. Morphological characterization of biotypes will help determine the effectiveness of biological control programs involving M. aethiopoides. none