No Question About It, It’s Just Chillin’

Sunday afternoon I noticed something as it went to an oak limb over the driveway. I walked over to get a closer look and saw this…

camouflage 1

Can you see it? (click photos to enlarge)

You see it, don’t you? Look closely:) Okay, if you did see it, you are good, because it resembles one of the brown leaves on the oak branch. I circled the object of interest in the image below.

camouflage with circle

Now can you see it?

It is a butterfly – a Question Mark, Polygonia interrogationis. Question Marks and Commas are members of the anglewing group of butterflies, named for the irregular outline of their wings. The common names come from the silver punctuation marks on the underside of their wings.

qadult question mark

Question Mark, winter form, wings spread

This time of year, when the wings are open, Question Marks have bright orange and brown coloration. When viewed from above, they can be distinguished from their close cousin, the Eastern Comma, by the presence of a black dash above the outermost black dot at the bottom of the bright orange patch of the forewing (Commas lack the dash). They also tend to have more angular-shaped wings and longer tails than Commas. This image shows the typical winter form of the Question Mark – the upper hindwing of the summer form is mostly black with short tails; the winter form is orange/black with longer violet tipped tails.

Question Mark - wings folded winter form wider view

Question Mark resembles a dead leaf when wings are folded

When the wings are folded and closed, the Question Mark becomes an excellent dead leaf mimic. The wing outline resembles the twisted shapes of adjacent leaves and the color blends nicely, even in the changing light throughout the day. I saw this butterfly fly up to the oak limb Sunday afternoon. It moved around for a few seconds and then sat still, immediately blending into its surroundings.

Question Mark - wings folded winter form

Question Mark in late afternoon sunlight

I checked on it a little later as the sun was setting and it was still in the same spot. It was cold Sunday night so I went back out Monday morning – still there. I checked again yesterday at sunset, thinking it probably had flown with the warming daytime temperatures – nope, still there.

question Mark - wings folded winter form 2

Question Mark in same position on a cloudy morning

And again, just a few minutes ago, it is still there. It has been almost 48 hours – amazing. This species is one of our few butterflies that overwinters as an adult so you may see them flitting about on warm winter days where they feed on tree sap, rotting fruit, and animal scat. I had always assumed they passed the cold days hidden in hollow trees or under loose bark. I will be curious to see how long it stays out on this branch. The more I learn, the more amazed I am at what goes on outside my woodland home.

They Grow Up So Fast…

Bumblebee Moth egg

Snowberry Clearwing Moth egg

Question Mark egg 1

Question Mark egg

It seems like just yesterday they were just a gleam in their parents multifaceted eyes, and then, before you know it, they are off to pupation college. I reported on some egg-laying of butterflies and moths in recent posts and decided yesterday to go out and look for the young ones out in the garden. It has been about three weeks since I photographed the eggs. Most lepidopteran eggs hatch within 3-5 days after being laid and many species of butterflies and moths have larval stages that last about two to three weeks. So, I expected to find some caterpillars that were in the mid to late instar stage of development. I did find a couple, and while I can’t be sure they are the ones from the eggs I photographed, they probably are from eggs laid about the same time.

Snowberry Clearwing larva mid instar

Snowberry Clearwing larva

The species I nicknamed Little Spike (a Snowberry Clearwing Moth larva) has become more proportional to its caudal horn (tail spike) and changed color. I cannot find any reference as to the function of the tail spike found on most sphinx moth larvae, other than one tongue-in-cheek mention that it must be to scare gardeners. Indeed, there is a common misconception that these types of caterpillars can sting you with that horn (they cannot). Perhaps it is similar to the angled stripes that many species have along their sides and serves to help break up the typical caterpillar outline or shape by blending in with leaf veins, petioles, etc. Notice that this larva does exhibit a form of counter-shading, with the color becoming fainter as you move from the bottom to the dorsal side of the body. Since this species often feeds on the underside of the light-colored leaves of honeysuckle plants, this color scheme makes sense, especially when viewed from below the leaf, causing the caterpillar to blend in more with its surroundings.

Question Mark larva late instar

Question Mark larva late instar

Next I looked over the elm sapling where I had found the Question Mark or Eastern Comma eggs (they are identical). It turns out they were laid by a Question Mark. The caterpillar is a rather fierce-looking larva armed with branching spines (scolia). I had to check the field guide to make sure it is not one of the so-called stinging caterpillars (like Io Moth or Saddleback Caterpillars) whose stiff spines contain venom which can cause severe irritation when touched. This species is, indeed, harmless, but the spines undoubtedly serve to protect it from many invertebrate predators and perhaps deter others.

Question Mark larva late instar 1

Question Mark larva posture

This particular caterpillar also had an interesting behavior when disturbed. It arched its body in a tight curve and stuck out the posterior end. I have seen some caterpillar species do this that can exude distasteful chemicals from their anus, or that have fake heads on their backside. I’m not sure if this is a species level behavioral trait or what the function might be if it is, but anytime I am faced with an array of sharp spines, I think twice before grabbing.