This August I found this long-nosed beetle in a patch of oak trees. Although it looks dangerous with a snout almost as long as its body, you should "fear no weevil," for it attacks only plants. With its long slender beak and its sharply elbowed antennae, it is identified as a nut and acorn weevil, a member of the genus Curculio with over 30 species on our continent. Many of these make their living on oaks.
|Curilio female weevil. Females have the longer beak|
Once out of the bag, it laid still for a minute and then started to make its getaway, looking for some nice soil to pupate in for a couple of years. It was slow moving so I had lots of time to set up for this macro movie to document its progress.
|Inserting the egg -click to enlarge- USFS|
Life begins for a weevil when a female bores into a green developing acorn and deposits a single egg. She seals up the tiny hole with her fecal material and the larva will emerge from the egg to find shelter and sustenance. After consuming most of the nut's contents, it carves out a round hole and struggles out of the acorn. The larva will then crawl off into the soil to pupate.
|Larva emerging an acorn - Jay Barber|
|Larva in acorn - USFS|
The whole process is shown in this short National Geographic video.
A fun fall activity is to collect acorns and crack them open to find weevil larva. Put them in a pan of water and save the ones that float to crack open for the larva. The space that the larva has chewed out makes them buoyant. On the other hand, if the sink "you will see no weevil". Sorry......no, not really