Wednesday, September 9, 2009

Milkweed Insects

Me: "Hey Chris, there's a neat bug over on the milkweed. Would you grab the macro and snap a picture?"

Chris: "Another one?"

What can I say? Milkweeds are full of interesting insects. I guess I keep noticing them because I have been checking our milkweed volunteers daily for monarch caterpillars.

These were the some of the first to catch my eye:



Euchates egle, the milkweed tussock moth, or harlequin caterpillar. These are a North American native. It turns out that monarchs don't care for tough, old milkweed, but these furry fellows love it.


They are a lively bunch, chewing and chewing; and when they see you coming, they go sprinting for cover.


These caterpillars usually aren't solo, and can be quite efficient at defoliating entire milkweed plants. But it's worth losing the plant, because these bugs are so much fun to watch in action.

The first time I saw one of the next critter, it was eating a hole in the one and only milkweed blossom in the yard. When I tried to photograph it, he dove into the flower in terror.


It's a red milkweed beetle, Tetraopes tetraophthalmus. On this occasion, we spied them on milkweeds over at Idylbrook Field. It was a chilly morning, so this and other bugs were too sluggish to escape our nosy camera.

Idylbrook Field is absolutely covered with milkweeds, including many tender young plants, the perfect food for tender young monarchs.


Aren't they cute? They look like Miyazaki characters.


The big ones are so plump and colorful!


Now if you don't care for swarms, you may want to skip the next several photos.

The orange bumps above are aphids. Specifically, Aphis nerii, oleander aphids. They likely originate in the Mediterranean, but (to my rather uneducated perspective) seem to be fitting in nicely into the local food chain. Supposedly they don't do much harm directly to milkweed, unless their population explodes, in which case their decomposing poop can block the leaves from getting ample sunlight.

Aphid poop, called honeydew, is mostly sugar. Ants love it, so they often swarm about overtop of the aphids, eating the honeydew and protecting the aphids.

This is a population of aphids that has exploded. The poor plant is rather encrusted with moldy honeydew.


Aphid swarms are all clones of the original female. The aphids continually give live birth to more clones until the host plant is too damaged, at which point the aphids produce clones with wings. Above, you can see one of the aphids has just given birth to a clone.


Wasps of some sortwere regular visitors to the swarmed plants. I believe they were eating the honeydew from the leaves.


This, I suspect, is some sort of assassin bug, of the family Reduviidae. It was likely there to dine on aphids.


I have no idea what this critter was, but the way it was crouched near the aphids makes me suspect it was there to make a lunch of them.


Here is the same bug, with a clueless aphid climbing over it's back.

Now enough with the nasty swarms! Here is something more attractive:



This is a yellow-collared scape moth, or Cisseps fulvicollis. It actually doesn't have anything to do with milkweed, even though it happens to be sitting on one.

I stumbled over two of them a few inches from each other on a milkweed (and who I feel guilty for interrupting); and nearby, another pair on some other sort of plant.


Woo, bug porn!

3 comments:

Pam J. said...

wonderful variety. and great photography! I like September for its colors and late bloomers.

hero爺 said...

Amazing!
You have many kind of insects in your garden!

MrILoveTheAnts said...

The ants on the aphids look like Prenolepis imparis. The Winter Ant. Expect to see more of them as it gets colder out.