Nesting behaviour of a subsocial African ball-roller Kheper platynotus (Coleoptera, Scarabaeidae)

ABSTRACT. 1. The nesting behaviour of Kheper platynotus (Bates) was observed in the Tsavo West National Park, east Kenya.
2. The construction of the brood ball seemed to be initiated by the female; thereafter, the male joined in. After its construction, the ball was rolled and buried by the male, whilst the female rode on the ball and occasionally helped the male.
3. After burying the ball, the male came out on the ground, leaving the female under-ground. The female coated the ball with soil and her excrement, and let it ferment for about 2 weeks. Thereafter, the female converted the ball into one to four free-standing brood pears, and laid one egg in each pear. The number of pears produced depended on the size of ball. Even after oviposition, the female remained in the nest to care for the brood.
4. Oocytes matured a little before being laid. Excess oocytes were gradually assimilated during brood care.
5. Females seemed most likely to breed in two or more successive rainy seasons.
6. Although male-male aggression was observed, size assortative mating was not observed.