Post-embryonic Development of the Seminal Vesicle in the Stingless Bee Melipona quadrifasciata Lepeletier, 1836 (Apidae: Meliponini)

Abstract

The male accessory glands of stingless bees (Apidae: Meliponini) are absent and the morphology of their seminal vesicle indicate probable secretory function by this organ. This study investigated the post-embryonic development of the seminal vesicles in males of the stingless bee Melipona quadrifasciata by histology and histochemistry. White-eyed pupae, pink-eyed pupae, brown-eyed pupae, black-eyed pupae, newly emerged and sexually mature males were studied. Seminal vesicle has a wall with a single layered epithelium onto a thin basement membrane, followed by a well-developed muscle layer. The epithelium is polarized in the pupal stage with basal cell region strongly positive for glucoconjugates and carbohydrates. The seminal vesicle has an enlarged lumen from the young pupal stages with luminal content increasing gradually with glucoconjugates along the pupal development. In the newly emerged and mature males, the histochemical tests to carbohydrates were negative. In the sexually mature males, spermatozoa clusters are embedded by the glucoconjugates content of the seminal vesicle lumen. In conclusion, the seminal vesicle of M. quadrifasciata has a secretory function during the pupal stage and in newly emerged males, whereas in adult males this organ stores the spermatozoa..

Developmental Differences on the Internal Reproductive Systems between the Prediapause and Prereproductive Riptortus pedestris Adults

“…It has been found that the spermatozoa were continuously produced even during the mating state, and the newly eclosed males store the spermatozoa in the lumen of the vas deferens [ 25 ]. In the pupal stage of stingless bees (Apidae: Meliponini), the male accessory glands are absent and the secretory function of this organ is performed by their seminal vesicle, whereas in the adult males, the accessory glands also store the spermatozoa [ 26 ].In the current study, the development of the accessory gland and ejaculatory duct in prediapause males was poor compare to prereproductivemales. It can be argued that the delay in reproductive development may result in the absence of hormonal productionduring the diapause period, which needs to be explored in future investigations.…”

Structural Changes in the Male Reproductive Tract of the Stingless Bee Scaptotrigona xanthotricha Moure 1950 (Meliponini, Apidae) During Sexual Maturation

“…In the Neotropics there are more than 400 species into 32 genera (Camargo, 2013), which performing fundamental ecosystem services as pollinators (Michener, 2007;Freitas et al, 2009) pollinating 40-90% of native plants (Brosi et al, 2009) as well as some crops (Slaa et al, 2006). The morphology of the male reproductive tract has been described in some species of Meliponini (Cruz-Landim, 2001; Dallacqua & Cruz-Landim, 2003;Ferreira et al, 2004;Araújo et al, 2005;Lima et al, 2006;Lino-Neto et al, 2008;Brito et al, 2010;Ferreira et al, 2019). Although those studies have contributed in some extension to understand the reproduction Moure, 1950 (Meliponini, Apidae) During Sexual Maturation in these insects, they are restricted to few species and gaps about the reproductive biology and evolutionary history of stingless bees needs to be fills.…”

“…An intriguing finding in the male reproductive tract of stingless bees is the absence of accessory glands (Kerr, 1948;Ferreira et al, 2004Ferreira et al, , 2019. In insects, the accessory glands associated with the male reproductive tract produce compounds that are involved in functions such as spermatozoa maturation and activation, sperm and spermatophore formation, activation of oviposition in females, polygamy control including the formation of the mating plug (Chen, 1984;Gillot, 2003;Boosmam et al, 2005;Colonello & Hartfelder, 2005;Fuessl et al, 2014).…”

“…In insects, the accessory glands associated with the male reproductive tract produce compounds that are involved in functions such as spermatozoa maturation and activation, sperm and spermatophore formation, activation of oviposition in females, polygamy control including the formation of the mating plug (Chen, 1984;Gillot, 2003;Boosmam et al, 2005;Colonello & Hartfelder, 2005;Fuessl et al, 2014). Because these glands are absent in stingless bees their function has been suggested to be replaced by secretory cells in other reproductive tract regions, mainly in the vas deferens and seminal vesicle (Dallacqua & Cruz-landim, 2003;Araújo et al, 2005;Brito et al, 2010;Ferreira et al, 2019). In these organs, the epithelial cells seem to produce components of the semen fluid (Dallacqua & Cruz-Landim, 2003;Araújo et al, 2005;Brito et al, 2010).…”

“…In social bees the spermatogenesis begins in the pupal phase and is completed in adult males with different ages according to the species (Happ, 1992;Cruz-Landim & Dallacqua, 2002;Dallacqua & Cruz-Landim, 2003;Lino-Neto et al, 2008). Males emerge sexually immature and continue to undergo structural changes in the reproductive tract until complete formation and migration of spermatozoa to the seminal vesicles, when they then are sexually mature to mate and fertilize the eggs (Araújo et al, 2005;Lima et al, 2006;Brito et al, 2010;Ferreira et al, 2019).…”