Thursday, October 15, 2009

Nut Weevil -- Curculio sp.

Acorn weevil meets leafhopper (9/11/09).

These robust-bodied, long-snouted weevils are fairly easy to identify to the genus level (Curculio), but a species ID is more difficult, though I think these are Curculio proboscideus. If so, several different species of oaks are their host plants.

A female has a longer rostrum (snout, beak) than a male, longer than her body. (Total length including rostrum is around half an inch.) The apex of the female's rostrum includes cutting apparatus that allows the drilling of a deep hole in a nut or acorn; eggs are then laid in the hole. Various species specialize in the nuts or acorns of particular species.

Shorter rostrum indicates this is probably a male.

Each female lays about 25 eggs which hatch in about one week. Larvae feed 6 to 10 weeks then chew their way out of fallen nuts and enter the ground where they spend the winter and spring. Larvae pupate in late spring and early summer. Adults begin to appear about the first of August.  There was an approximately 10 day period in mid-September when these weevils were numerous under our porch light.

An extremely long rostrum indicates this is almost certainly a female (9/16/09).



Lisa at Greenbow said...

What a funny looking weevil. I just love that first photo with the weevil meeting up witht he leafhopper. The leafhopper has such a unique color. Ain't nachur grand??

Shelly Cox said...

I LOVE LOVE LOVE that first picture! The clarity of the weevil is amazing! Great shot. Weevils are such interesting subjects to photograph.

John B. said...

The weevil is a very odd looking insect. Great work getting that and the leafhopper in the same frame!

SAPhotographs (Joan) said...

What a great shot getting the two of them together in one Marvin. I have never seen one with such a long nose. My goodness!! How does she manage to find her way through a leafpile? :) Excellent info too. Thanks.

Unknown said...

Bugs are a marvel when you look at them like that: great close-up photography as usual. Must be cold up there judging from dose of cold air here in south Florida!

Texas Travelers said...

Outstanding photographs !!!

Great post and thanks for sharing this wondrous venture into the realm of natures small but fascinating and beautiful creatures.

BTW, thanks for the visit and nice comment about the 'square headed' ants.

Troy, in a very chilly Ft. Worth this morning.

Lana Gramlich said...

Wow...such strange looking creatures. Thanks for all of the info, as always. It's not just a blog, it's a mini-lesson!