#1493 - Tranes sp. - Zamia Weevils
Photo by Anna Neko, in Bold Park, Perth. Probably Tranes vigorsii, based on location.
Small weevils that are one of the specialist pollinators of Macrozamia and Lepidozamia cycads, ancient seed-bearing plants with palm-like leaves. Cycad seeds are quite poisonous, thanks to the effort of cyanobacteria in their roots, but that hasn’t stopped people from collecting them as food (after extensive preparation) because if you’re hungry enough you’ll learn how to eat anything (at least once).Â
The other specialist pollinator for these Australian plants are thrips in the small three-species genus Cycadothrips. Some of these cycad species utilise only the weevils, or only the thrips, while others use both. The weevils feed on the cones of male plants, and visit the female cones, often in large numbers. There’s some evidence that the female plants use chemical cues to attract the weevils when they’re ready to be pollinated, then drive them off again to avoid damage to the ovules after they’ve been pollinated..Â
There’s 11 known species of Tranes in the world, and 4 in Australia, which implies that some of them are up to the same kind of work in other parts of the world, for different genera of cycads. I just haven’t got any information on the species overseas.Â