Morphostructural investigation on spermatozoa and sperm bundles of the leafhopper Balclutha brevis Lindberg 1954 (Hemiptera: Deltocephalinae)

Abstract

Morphostructural investigations on male gametes and sperm bundles of Balclutha brevis Lindberg 1954, allochthonous species in Sicily and in mainland Europe, were carried out by light and electron microscopy, since few and fragmented data are known in this respect on leafhoppers, particularly of the subfamily Deltocephalinae. The peculiar feature of the structural organization of B. brevis spermatozoa, for the first time shown in detail within Deltocephalinae, is the presence of apical blebs at the anterior tip of the gametes; moreover, a branching of the flagellar end piece is observed. The sperm bundles of B. brevis, whose genesis occurs in the follicular cysts, also have a peculiar organization within the Cicadomorpha. In fact, the gametes of the bundles are held together by means of membrane junctions between their apical blebs. Sperm bundles remain unchanged up to the lateral ejaculatory ducts where they undergo a rapid disorganization and the gametes, mostly free, are transferred into the female bursa copulatrix and then into the common oviduct, awaiting fertilization. Some spermatozoa isolated from the bundles are found in the seminal vesicles where a spermiophagic activity by epithelial cells is hypothesized.