Tag: monarch larva

Bug of the Week: Comparing Milkweed Caterpillars

This week we had two caterpillars on our rush milkweeds.

stripy-2-caterpillarAt first glance they look quite similar.

stripey-3-caterpillarBoth have bands of color and filaments (also called tubercles) that look like antennae.

stripey-2-47Looking more closely, it is apparent that this caterpillar has two pairs of filaments, one pair in front and one pair in back. In addition, its bands of color are unbroken.

stripy-three-68This caterpillar has three pairs of filaments and some of the dark bands have droplets of yellow in them.

Do you know what species of caterpillars these are?

Note on the filaments (tubercles):  These threadlike projections are often mistaken for antennae. Caterpillars do have antennae, but they are only tiny bumps on the front of the head near the mandibles. The filaments vary in length and are occasionally missing.

Caterpillars like these can move their filaments, sometimes in a jerky motion.

Answers:  The caterpillar in the first and third photographs will turn into one of these. The caterpillar in the second and fourth photographs is one of these.


Bug of the Week: The Mix Unscrambled

Last week I gave you two photographs that were teeming with insects. Many of you recognized the orange-yellow bumps were aphids.

Okay, it is very small, but between the legs of the butterfly is a newly hatched caterpillar. See the little guy with the black head at the arrow tip? It is a monarch butterfly caterpillar.

In this video, you can see one hatching under a microscope. (Video has music).

Another insect is hidden within those dark-colored aphids.

See the ones that are black or dark red? They are parasitized, which means they are carrying a tiny wasp larva inside them.

Eventually the dark aphids will stiffen and cling to the stem. In that stage they are called an aphid mummy. After a few days the larvae inside will complete its life cycle, pupate and then emerge as an adult wasp.

Photograph by Sarefo

You can see where a wasp emerged from this aphid mummy through the round hole in the back.

Here’s the tiny wasp that emerged from the hole. She will lay her eggs in yet more aphids, resulting in yet more aphid mummies.

Finally, there is one other interesting thing about this picture. See that the butterfly has its mouthparts extended? I watched this butterfly for several minutes before taking its picture. It was sucking up the honeydew from the aphids.

We got to see all this because we planted a special plant in our yard. Do you have any plants that attract insects in your yard?