Bionomics and rearing of Miltotranes prosternalis (Lea, 1929) (Coleoptera: Curculionidae), a mutualistic cycad pollinator in Australia

Abstract

Pollination is the crucial stage for reproduction and survival of plants, therefore knowledge about the bionomics of pollinators is often critical for plant conservation. Bowenia spectabilis (Cycadales: Stangeriaceae) is a CITES-protected cycad species endemic to the Wet Tropics Bioregion of Queensland, Australia. It is pollinated by a host-specific weevil species, Miltotranes prosternalis (Lea, 1929) (Curculionidae: Molytinae), which breeds in its male cones but also visits its female cones and pollinates them. The association between the cycad and the weevil is an obligate brood-site reward pollination system, in which the weevil is provided with food and a brood site by the plant in “return” for the service of pollinating it. To facilitate the knowledge of the natural history of this unique Bowenia pollinator, we developed a method for rearing mature larvae of M. prosternalis collected from the field in the laboratory. Furthermore, we summarize biological information of M. prosternalis gathered from previous studies and by firsthand observations in the wild and during rearing in captivity. Show more