Morphogenesis of the flagellum in the spermatids of Coelomera lanio (Coleoptera, Chrysomelidae): ultrastructural and cytochemical studies.

The flagellum of Coelomera lanio has a single axoneme with a 9 + 9 + 2 axoneme pattern and the microtubules are linked to the E-PTA positive dinein arms. The electron-dense fibres between microtubules show a positive acid phosphatase reaction. A single E-PTA positive accessory body is seen flanking the axoneme, from which extends a puff-like corpuscle. On the opposite side of the accessory body, away from the axoneme, exists another puff-like corpuscle. The mitochondrial complex gives rise to two mitochondrial derivatives of different shapes and sizes. The major derivative possesses a paracrystalline corpuscle and the minor has an electron-dense area in the juxta-axonemal region. All these structures are involved in the mechanism of flagellar motility.