Like Apis mellifera queens and different from all other bees, drones also have an exaggerated gonad phenotype, with over 150 serial units in each gonad. Yet, compared with the ovaries of the female castes, little is known about the development of the honey bee testis. Here we present a histological atlas on postembryonic testis development and spermatogenesis. Already in the first instar larvae, the testioles composing each testis can be distinguished. The testioles then grow along their apical-basal axis by mitotic divisions of the spermatogonia, which eventually form germ cell clusters. Meiosis starts when brood cells are capped, and it ends with the appearance of spermatids in red-eyed pupae. Subsequently, spermiogenesis takes place, and all spermatozoa are formed before adult emergence. We also present the first data on juvenile hormone levels in drone larvae. With this, we provide a database for future research on gonad development in honey bee drones.

中文翻译：

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蜜蜂雄蜂的睾丸发育和精子发生，Apis mellifera L。

与蜜蜂蜂王后不同，雄蜂也有夸张的性腺表型，每个性腺有 150 多个序列单元。然而，与女性种姓的卵巢相比，人们对蜜蜂睾丸的发育知之甚少。在这里，我们提出了关于胚胎后睾丸发育和精子发生的组织学图谱。已经在第一龄幼虫中，可以区分组成每个睾丸的睾丸。然后睾丸通过精原细胞的有丝分裂分裂沿着它们的根尖轴生长，最终形成生殖细胞簇。减数分裂在育雏细胞被覆盖时开始，并以红眼蛹中精子细胞的出现结束。随后，发生精子发生，所有精子在成虫出现之前形成。我们还提供了有关雄蜂幼虫保幼激素水平的第一个数据。有了这个，我们为蜜蜂无人机的性腺发育的未来研究提供了一个数据库。