Morphology of the internal reproductive system of the male and female two-spotted stink bug, Perillus bioculatus (F.) (Heteroptera: Pentatomidae) and the transfer of products during mating

Abstract

Summary The reproductive systems of male and female Perillus bioculatus are typical for the Pentatomidae. A detailed examination of the spermatheca revealed that the duct assembly acts as a valve. When the valve is open, male secretions pass into the spermathecal pouch, but in the closed position sperm pass through the spermathecal duct extension and enter the spermathecal bulb. Males have a composite ejaculatory bulb that is composed of dorsal and ventral units. The dorsal ejaculatory bulb is formed by tissues that are continuous with the walls of the outer ejaculatory duct. Extensions from the dorsal bulb form the medial and lateral ejaculatory pouches. Ectadenia open into the dorsal bulb and their secretions fill the ejaculatory pouches which increase in volume from 3.5 days post-emergence as the male matures. The ventral ejaculatory bulb is muscular and receives the seminal vesicles. Mesadenia open into the seminal vesicles and their secretions, along with sperm, pass through the ventral ejaculatory bulb. The ejaculatory duct consists of outer and inner units. The outer unit is a continuation of the dorsal ejaculatory bulb while the inner unit is a continuation of the ventral ejaculatory bulb. During mating, the male genitalia clasp a tubercle on the vaginal genital plate that contains the opening of the spermathecal duct and materials from the male are introduced directly into the spermathecal duct. Within 1.5 h of mating, male ejaculatory pouch volume decreased 86%, but were completely recharged within 24 h of the completion of mating. Spermathecal pouch volume increased more than twofold after mating for 0.5 h. Three soluble glycoproteins, pi, p2, and p3, with molecular masses of 101.9,86.3, and 72.8 kDa, respectively, were stored in the ejaculatory pouches and transferred to the female spermathecal pouch during mating.