Ovarian condition as an indicator of the phenology of Bubas bubalus (Coleoptera: Scarabaeidae)

Bubas bubalus (Oliver) is an important agent of dung dispersal in pasture habitats. Newly emerged females show little differentiation in their single ovariole. When environmental conditions are favorable (after rainfall and with mild temperatures), the oocytes mature sequentially. There is a significant correlation in size between the terminal and subterminal oocyte. When the terminal oocyte is laid, it leaves a yellow body inside the neck of the ovariole (calix). Yellow body accumulates as the laying period progresses. During adult life in response to stress, B. bubalus females resorb the oocytes; this resorption can be from either inside or outside the ovarioles. The latter is more frequent, and it suggests an important adaptive advantage.