Tiger Swallowtail Caterpillar

I'm not a monster, I was born this way! Well...sort of. During my first few
growth stages I was going through this whole bird dropping mimic thing -
gross! But then I watched like 400 of those It Gets Better YouTube videos.
Now, I've unleashed the beast! Finally free to be me!

A friend sent me this picture last week. She took it while visiting at her parents' house in Blacksburg, VA (Go Hokies!). They weren't sure what this critter was, so they were initially calling it the mini-monster. But after it professed an intense affinity for Lady Gaga's music, they took to calling it their Little Monster.

While this Little Monster may be experimenting with his identity right now, he will eventually grow up to be a fabulous Tiger Swallowtail butterfly. For now, he's displaying some of nature's finest mimicry. Snake-mimicking is one fascinating characteristic of swallowtail caterpillars. If you find it hard to discern a caterpillar from this picture, then you have something in common with many insectivores (congratulations!). This caterpillar's head is the grayish ellipsoid at the lower end (as he's situated in the picture) of this critter. The yellow circles are just yellow circles (the red collar (or smile) is just coloration, too). He hasn't even developed the compound eyes that he'll have as an adult - he just has small clusters of simple eyes on either side of his true head (these true eyes are not visible in the picture). Now Tiger Swallowtails do a pretty neat job of mimicking snakes (maybe a ringneck snake (Diadophis punctatus), specifically?), but other swallowtail species' caterpillars will take the ruse in impressive directions. Some mimic the triangular heads of venomous snakes or have coloration patterns that look like snakeskin.

Adult Eastern Tiger Swallowtail, courtesy of Andy Emcee, via Wikimedia
Commons. This female is using her long proboscis to drink nectar from the
flower. Perhaps fueling up for Carnivale? I used to work with a guy who
wore super matchy, over-coordinated suits like this, but I never saw him
decked out for a trip to Rio like she is! Get her a crazy hat & thong and
she'll be ready for the parade. Come on Tiger Swallowtail, no one likes a
show off.

But this is definitely the caterpillar of a species of Tiger Swallowtail butterfly. Incidentally, the Tiger Swallowtail is considered the official state butterfly of Virginia. So this petite patriot (state-riot?) may have been on my friend's parents' southwest VA front porch as part of a door-to-door effort in support of one of the gubernatorial campaigns. I wonder which side he was working for (nobody say Green Party - not creative enough to be funny!).

It's no surprise that this Tiger Swallowtail caterpillar is such a big Lady Gaga fan. They have quite a bit in common. They're both known for reinventing themselves (can I get a whoot-whoot for pupation!). They both wear garish colors - the yellow adults' style is very last season (and the style of the adults from last season is very season-before-last) and the caterpillars are a very bright green until they're about ready to pupate (whoot-whoot!). Lady Gaga and swallowtail caterpillars are both excellent at mimicry. Gaga's well known mimics include meat (appropriate awards-show attire), Madonna (a much more dangerous pop star), the Thunderdome (I don't recall this outfit including a diminutive Tina Turner, or an even more diminutive Master (sans Blaster)), and bubbles. Ms. G often uses her camouflage to impress or intimidate hordes of pan-sexual urban 20-somethings. I've already written quite a bit about the swallowtail caterpillar's mimicry. But in addition, this caterpillar's chrysalis (like a smooth cocoon without silk) is exquisitely well camouflaged to look like a twig (a Disco Stick?), often with intricate coloration and even lichen-like mottling. Swallowtail caterpillars also have their own signature scent. If they feel threatened, they can rear up on their back legs (6 front legs, 10 prolegs in the back that it will lose during pupation (whoot-whoot!)) and evert their osmeterium (do what?). The osmeterium is a brightly colored and aromatic scent gland. When they "inflate" this organ out from a hidden duct behind their head, it looks like a snake's forked tounge (and really stinks up the place). Due to its appearance, this gland is sometimes referred to as "scent tentacles," but I'm pushing for scentacles (did you say Santa Clause?)! Finally, caterpillars share with Ms. G a strong aversion to wearing pants (I counted out all their legs a few sentences ago...what's your excuse, G?). In fact, the obscenely underclothed caterpillar in the picture above was on its way to the airport (hi-ooooooh! Waiting on Perez to Tweet up #BugsIRL)!

Let's get serious for a moment - this is a serious blog for serious people and I am sick of all this skylarking! The Eastern US hosts several species of Tiger Swallowtail. Differentiation between adults of the different species is not trivial, the indicators are subtle and only observable from close up. I'd say that the best way to differentiate between the species as larvae is to wait for them to pupate (whoot-whoot!), then wait another one to two weeks (or until the following Spring, if you're observing the final generation of the season) for them to emerge as adults. Failing that, we can play the likelihood game - which is often useful, but not nearly as fun as Hungry Hungry Hippos or Candyland. Speaking of Candyland, I'd like to make a confession: I, Brian MacBugsmansonsten, am a Hasbro-certified cheatsman. Yes - I have grifticulated like a no-good splinterhead. While I was elementary school aged, I would often visit my cousins who lived near by. While visiting, it was pretty typical for us to hit a few rounds of Candyland. In nearly every round played, over a number of years, I would always manage to stack the deck of cards so that I would draw Queen Frostine on my first turn - this jump-to way-point was the closest one to the finish line because, as I recall, my cousins' game no longer had the card for Molasses Swamp because one of them was afraid of Gloppy the Molasses Monster. As I said, this ruse went on for several years. But by the end, I think I wanted to get caught.

Anyway, back to the bugs (and seriousness)! Tiger Swallowtails are not migratory like their cousin the Monarch Butterfly (who I hear is also so afraid of Gloppy that their dad had to remove that card from the deck), so that leaves three species that my friend's Little Monster is likely to be. The first possibility is the Canadian Tiger Swallowtail. Although it's range extends south along the Appalachians, I haven't come across a map that shows it quite as far south as Blacksburg. The second possibility is the Appalachian Tiger Swallowtail, which was formerly considered to be a subspecies of the Eastern Tiger Swallowtail (door number 3). However, it's my understanding that this species is limited to a single brood that lives only in the mountains of western North Carolina - which is about as far from Blacksburg as I've seen the range of the Canadian Tiger Swallowtail extend. This leaves the third possibility: the Eastern Tiger Swallowtail (Papilio glaucus), whose range cleanly overlaps Blacksburg and the surrounding areas  (who chose this ordering? why couldn't we have just started with the most obvious one?).

So, with another mystery solved, it's time for me to leave you with a parting thought. But first, I want to thank everyone who's sent me bug pics with ID requests. If I haven't gotten to your request yet, know that it's in the works and I will get to it soon. If you have an ID request or just an awesome bug pic that you want to share, please send me an email at WhoDatBug@gmail.com.

Don't slow! Drive it, clean it, lights out, bleed it. Spend the lasto. I got it. In your pocko. I got it.
 - Stefani Joanne Angelina Germanotta (Just Dance, 2008)