Light and Electron Microscope Observations of the Male Reproductive Organs of Adult Julodis ehrenbergii Laporte (Coleoptera, Buprestidae).

Abstract

This paper was the first preliminary description of the male reproductive organs in Julodis ehrenbergii Laporte (Coleoptera, Buprestidae) using light and scanning electron microscope techniques. The structure has a couple of testes, a couple of vasa deferentia, a couple of accessory glands, a couple of spermatophoral glands, and a single ejaculatory duct opening in the aedeagus. Each testis is made up of many elongated testicular follicles. Our histological observation showed cysts at different stages of development in the testicular follicles. In other words, spermatocytes, spermatids, and spermatozoa, respectively, are formed from the spermatogonia located at the distal end of the testicular follicles. Mature sperm bundles were observed in the lumen of the vasa deferentia. The male accessory glands are curved and thin tube-shaped. There are dense secretion granules in the cytoplasm of the accessory glands' epithelial cells. The spermatophoral glands are roughly oval-like structures and have three lobes on one side. The ejaculatory duct is characterized by the presence of the cuticle layer on the apical surface of the cells. The findings were compared with the male reproductive structures of some other species in the Coleoptera order. Some characteristics, including the number and shape of testicular follicles and accessory glands, among the species of the Coleoptera order, show differences. These features help allow future comparisons with the male reproductive organs of other Coleoptera species.