In this study, we aimed to describe the morphology of ovaries, and used histological approaches to define the ovary morphology and oogenic follicles, including the proportion of atresia of the golden tree snake, Chrysopelea ornata (Shaw, 1802). Morphological observations showed that the ovaries contained different stages of follicles, suggesting active ovarian activities during sexual maturation of the female snake. Half of the follicles in a paired ovary, where the oogenesis took place, were previtellogenic follicles. Multiple layered structures of the follicular cells in the previtellogenic follicles could be categorized into at least three distinguishable cell types based on cell size and shape including small cells, intermediate cells, and pyriform cells. The previtellogenic follicles continuously developed into early vitellogenic follicles where more uptake of yolk granules could be observed. In addition, ovaries also contained the atresia (atretic follicles) showing the irregular follicles and sign of yolk degeneration. The atresia can be found in about 37% of the total follicles. For the first time, this study focused on the ovarian histology and proportions of follicular types in the golden tree snake.
