Ovary structure and oogenesis in Heteroptera

ABSTRACT

Heteropteran ovaries are meroistic, telotrophic type and composed of several ovarioles that consist of a terminal filament, tropharium, vitellarium, and ovariole pedicel. The tropharium is made up of trophocytes, young oocytes and prefollicular cells, while the vitellarium consists of linearly arranged ovarian follicles (oocytes surrounded by follicular epithelium). Contact of the oocytes with the tropharium is maintained by nutritive cords. Despite the general similarity in the organization of heteropteran ovarioles, there are significant differences in the structure of the tropharium and vitellarium. In primitive groups of Heteroptera, the tropharium is composed of individual cells, while in more advanced taxa, the trophic chamber is built of syncytial lobes containing several nuclei (the exception is Miridae). The vitellarium consists of a different number of ovarian follicles, from one to 12. Oocytes develop either synchronously or asynchronously. The differentiation and diversification of the follicular epithelium differs even in closely related groups. The data so far comes from studies on representatives of 22 families (Heteroptera includes 87 families) and are usually only partial. To analyse the anagenesis of the heteropteran ovaries, research on representatives of the other heteropteran families from the studied infraorders should be carried out, and from Enicocephalomorpha whose ovaries have not been examined.

KEYWORDS:

• Telotrophic ovariole
• oogenesis
• tropharium
• vitellarium
• follicular epithelium

Disclosure statement

No potential conflict of interest was reported by the author(s).