Within the order Coleoptera, or beetles, the weevils constitute a most interesting group. Also called snout beetles, weevils are characterized by having an elongated, downwards curving snout. Many weevils are serious pests of crops, seeds, and plants.
A much less destructive weevil is pictured at right. The acorn weevil is a beautiful little insect with a long, gracefully curved snout. They appear in late summer when the live oak acorns on a tree in our yard are ripe. The adults feed on the acorns by drilling a small hole into the fleshy part of the seed using rasping mouthparts on the end of their long proboscis. The female beetles lay their eggs inside a feeding hole, where the grubs eventually will hatch and eat the pulp of the acorn.
The final insect shown here is an oak leaf roll weevil. It is a robust, stout beetle, with a shiny porcelain-like finish to it's wing covers. The attractive red and black coloration makes the weevil easy to identify, even though we rarely see them. These weevils spend most of their time in the canopy of our largest live oak trees. The female lays a single egg on a young oak leaf, then scores and rolls it up to protect the contents. These leaf rolls are then severed from their attachment to the branch and they fall to the ground. I've found dozens of them on our back deck and carefully unrolled a couple that were fresh. They are very well constructed and most people can't do as well rolling up a sleeping bag. The end of the leaf is even tucked in so that it will not unroll and it takes some persistence to actually unroll one completely. Once the rolls have aged a couple days, if the weather is dry, the leaf dries into a hard casing around the egg. When it hatches, the weevil grub will eat the leaf and possibly even pupate within the roll.
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