Abstract Notonecta maculata is a backswimmer of the family Notonectidae . It is an aquatic predator that feeds on mosquito larvae and other soft‐bodied aquatic insects. In this study, the male reproductive system morphology of N. maculata was examined using both light microscopy (LM) and scanning electron microscopy (SEM) for the first time. The male reproductive system of N. maculata consists of a pair of testes, vasa deferentia , seminal vesicles, two pairs of accessory glands, an ejaculatory duct and an aedeagus. Each testis contains six follicles. Histological and SEM analyses revealed bundles of spermatozoa within the follicles. The testis follicles open into the slender and coiled vas deferens . The vas deferens is lined with a simple squamous epithelium, filling its lumen with spermatozoa. It forms a helical structure toward the end and transitions into the seminal vesicle. Just below the seminal vesicle are two types of tubular and coiled accessory glands (Ag1 and Ag2), which open into the ejaculatory duct. Ag1 comprises a simple cuboidal epithelium and contains basophilic secretions and secretory vesicles of varying sizes in the lumen. Ag2 is lined with a simple columnar epithelium; its lumen contains basophilic and eosinophilic secretory material. The ejaculatory duct consists of an intima, a simple cuboidal epithelium and a thick muscular layer. This study contributes to understanding reproductive morphology in aquatic Heteroptera and provides a basis for future comparative and taxonomic studies.
Koçakoğlu et al. (Tue,) studied this question.