Abstract:
The hatschek's pit is an important component of the reproductive endocrine regulation axis in
Amphioxus. In order to further reveal the relationship between the morphological characteristics of hatschek's pit and gonadal development of
Amphioxus, and enrich the biological basic information of
Amphioxus, the morphological changes of hatschek's pit at different stages of gonadal development of
Branchio-stoma floridae were observed by using the histological section and HE staining technique. The results showed that when the gonads of
Branchio-stoma floridae appeared at the beginning and early stage of development, the hatschek's pit was located near the notochord of
Amphioxus, with a thin film separating it, forming an approximately symmetrical inverted "concave" shape. During the development and mature period of gonads, the hatschek's pit had a thickened top, clear cytoplasm, enlarged on both sides towards the pit, smaller gaps within the pit, and a shorter and wider shape. During the period of gonadal emptying and degeneration, the two sides of the hatschek's pit were slender and the space inside the pit was narrow.