ケニアに生息する大型タマオシコガネ Kheper platynotus と K. aegyptiorum の繁殖行動
1988 年 1988 巻 32 号 p. 1-17
詳細
1988 年 1988 巻 32 号 p. 1-17
The nesting behaviour of African ball-rolling scarabs, Kheper platynotus (Bates) and K. aegyptiorum (Latreille), was observed in the Tsavo West National Park, east Kenya. Both species produce multiple brood pears from one buried dung ball, and take care of brood. Such a pattern of nidification has never been known in any other ball-rollers. The way of brood care is singular in that the mother beetle scrapes the upper part of the pear where larval excrement is accumulated.
In K. platynotus one to four pears are produced from a ball ranging from 5.2 to 9.0cm in diameter, and in K. aegyptiorum one or two pears from a ball ranging from 3.8 to 4.7cm. In the former species, the number of pears produced depends on the size of ball which is independent of the size of ball-maker.
Reproductive behaviour of male has been compared between K. platynotus and K. aegyptiorum. The former male attempts to copulate with a female above ground; seems not to be the initiator of the brood-ball construction; performs hind-leg bending behaviour on the dung pad without the function of attracting females; and makes no nuptial ball. The latter male does not attempt to copulate with a female above ground; to be the initiator of the brood-ball construction; performs hind-leg bending behaviour on the ball to attract females; and makes a nuptial ball.
