What’s With the Little Holes in Acorns?

I’m sure you’ve all seen acorns with small holes in them, often right under the cap, like on this one. What causes that? To the best of my knowledge it’s actually an insect called acorn weevil, an insect in the genus Curculio. The female lays her egg in an immature acorn. The larva develops inside the acorn, and then when the nut ripens and falls it bores its way out to live in the soil until it’s ready to mature into an adult. If you want to see what the weevil actually looks like, it’s actually the subject of possibly one of the greatest insect photos of all time. For more information, the Michigan Entomological Society has a great page on acorn insects.

And now, because I’m talking about a species of Curculio, I’m sorry but I cannot resist posting the weevil joke from the naval movie Master and Commander. Again.

Capt. Jack Aubrey: Do you see those two weevils, doctor?
Dr. Stephen Maturin: I do.
Capt. Jack Aubrey: Which would you choose?
Dr. Stephen Maturin: Neither; there is not a scrap a difference between them. They are the same species of Curculio.
Capt. Jack Aubrey: If you had to choose. If you were forced to make a choice. If there was no other response…
Dr. Stephen Maturin: Well then, if you are going to push me… I would choose the right hand weevil. It has significant advantage in both length and breadth.
[the captain thumps his fist in the table]
Capt. Jack Aubrey: There, I have you! You’re completely dished! Do you not know that in the service, one must always choose the lesser of two weevils!

You’re welcome.

The Lesser of Two What Nows?

It’s been years since I’ve seen the movie Master and Commander: The Far Side of the World, but two scenes stand out in my memory.  One is when the ship’s captain takes the wounded ship’s surgeon, who is also an amateur naturalist, to the Galapagos Islands to recuperate.  The other is the scene with the weevil joke.

Capt. Jack Aubrey: Do you see those two weevils, doctor?
Dr. Stephen Maturin: I do.
Capt. Jack Aubrey: Which would you choose?
Dr. Stephen Maturin: Neither; there is not a scrap a difference between them. They are the same species of Curculio.
Capt. Jack Aubrey: If you had to choose. If you were forced to make a choice. If there was no other response…
Dr. Stephen Maturin: Well then, if you are going to push me… I would choose the right hand weevil. It has significant advantage in both length and breadth.
[the captain thumps his fist in the table]
Capt. Jack Aubrey: There, I have you! You’re completely dished! Do you not know that in the service, one must always choose the lesser of two weevils!

Until recently I had never, to the best of my knowledge, actually seen a weevil, but then I started noticing these tiny insects around frequently.

I do mean tiny – less than two centimeters long.  If it gives you a sense of scale, those crystal-looking things it’s standing on are individual grains of sand.

Thanks to BugGuide, I know now that it’s Pachylobius picivorus, the pitch-eating weevil.  Apparently it feeds on young pines, especially in disturbed areas.  So what was it doing on the beach on the south end of the island, away from the area where most of the island’s pines are?  Maybe the wind blew it here?  I like the dotted line patterns on its back, but I don’t know if they have any significance.

I’m going to submit this post to the beetle carnival, An Inordinate Fondness.  My first time participating!  Also, the second plover from yesterday’s ID challenge remains a mystery – pull out your field guide and take a look! Never mind, the mystery has been solved.  Go look if you’re wondering.