SBFSEM of the mandible of Nasonia giraulti showing the basimandibular and genomandibular glands.

The class I basimandibular gland is located at the ventral wall of the mandible. The thickness of the mandibular cuticle abruptly decreases at a smaller region on its ventromedial side where the cuticle is five times as thin as at the surrounding regions. The area with decreased thickness is densely fenestrated by cuticular pores and is adjacent to enlarged, electron-dense epithelial cells with electron-lucent nuclei. On the SBFSEM micrographs of N. giraulti, the epithelial cells of the basimandibular gland are not detached from the adjacent, thin cuticular region. We did not observe any difference in the size of the basal mandibular gland between male and female specimens or specimens from different species.

The mandibular rods are solid structures that are continuous distally with the mandibular cuticle close to the tip of the mandibular teeth and do not connect proximally to any sclerite or muscle tissue. We did not locate any cuticular canals or densely pored regions in the rods and adjacent cuticular regions. 6–8 cellular structures with indistinct nuclei are connected to the base of each rod.