Parasitised and Mummified Slug Caterpillars (Cup Moths, Limacodidae), mummified (left) and normal appearance (right)

Despite all their bells, whistles and gadgetry aimed at protecting themselves, the prevailing nemesis of Limacodid caterpillars is parasitism. Parasitoids (parasites that kill the host in the process of completing their life cycle rather than reusing/reinfecting the host) have adapted specifically to these caterpillars and, in some cases, to individual species of Limacodids, to further their survival.

Wasps of the family Braconidae are one such example. One of the techniques they employ is “mummification”.

An egg is injected into the caterpillar by the female wasp and the hatched larva goes through its multistage growth cycle selectively consuming non-essential tissues of the caterpillar. To this point, the caterpillar may appear completely normal externally. When it comes time for the wasp grub to pupate and transition into the adult wasp, rather than erupt out into the world, the pupa is formed inside the caterpillar. By this time, the caterpillar succumbs to the alien growing inside it and dies. The developing wasp, however, chemically mummifies the caterpillar into a hardened shell which retains the shape and/or spiny defences of the former caterpillar. In other parasitoid situations where the mummification process is not employed, the carcass would just rot, dessicate and collapse, even be carried away by scavengers. However, part of this process turns the mummy bright yellow or orange. These colours scream “Danger!”, “I taste awful!”, “I am poisonous!” and “Don’t touch me!” in the eyes of nature. So not only does the wasp-to-be have a ready made incubator to metamorphose within, but it is unlikely that anything is going to disturb it or eat it, including other parasitoids.

These mummified carcasses can persist in place long after the adult wasp has emerged and moved on to the next victim. However, the otherwise flawless form is marred by a gaping hole through which the adult wasp has emerged.

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(above) A parasitoid Braconid Wasp (Spinaria sp., Rogadinae, Braconidae) surveys the empty shell of a Limacodid Slug Caterpillar incubator (Cup Moth, Demonarosa rufotessellata, Limacodidae) “Tank” which served as it’s host, larder and incubator.

by Sinobug (itchydogimages) on Flickr.
Pu'er, Yunnan, China

View my other images of Limacodid Caterpillars from China in my Flickr photostream HERE….

The winning design of my plush contest, the hamburger doggerpillar by Nora Meek! This one took about three days to make. My favorite part was figuring out the lettuce. I could have just made a flat piece that looked like a green flower but I wanted to go all out and make something I could be proud of.
I had to rearrange some of the ingredients from the original design so they would be more visible on the plush. I also made it so some of the ingredients would hang out a bit. The girth of the design is given by the tomatoes and meat paddy. I went ahead and made the paddy extra thick. The lettuce leaves dress it up rather well I think.

The plush is assembled with embroidery thread going straight through some of the ingredients to ensure that it won’t fall apart. If you were inclined on destroying it, you’re going to have a hard time unless you, yanno, use scissors or a knife. I would recommend against doing that.

Thanks to everyone who entered! I will be opening up commissions soon!

Flannel Moth (Megalopyge bissesa)

While this looks like something a mountain lion would cough up, its actually the larva of the flannel moth (Megalopyge bissesa). While many moths and caterpillars use camouflage or coloration to stay safe, the flannel moth caterpillar (sometimes called an Asp) is covered in urticating hairs, which break off and cause irritation like fiber glass. They also hide spines that are connected to poison glands which makes this genus one of North Americas more venomous caterpillars.

photograph by Tony Palmer | NPS

(via: Saguaro National Park, AZ)

behind the scenes of that caterpillar

This submission comes from someone who happened to work a bit on set. She/he asked me to remain anonymous, so I’m just gonna copy/paste this, because this is a really cute story. This caterpillar made my day!

When it comes to tumblr, I’m content to occasionally skim various fan interpretations of bloopers, unfinished scenes, writer/director soundbites, let ‘em be what they will be without comment. But I feel compelled to set the record straight and confirm – at least when it comes to the caterpillar – Gillian totally saved that little woolly bear’s life!!! She dropped out of frame to pick him off the ground the second Jim Wong called “cut”. David joked about whether it was poisonous or not but she was not swayed. I cannot account for the time between the end of that take and her managing to take photos of it by her chair, but for the next set up, she deposited that caterpillar onto the leaves of some shrubbery beside those porch steps out of harm’s way. I caught most of this on camera and like most any other human being, thought it was a very a cute moment. Normally, how does one justify taking up valuable runtime to setting up the minor detail of an actor saving a bug from being “scrushed” into a featurette? Luckily, Founder’s Mutation has a scene with Scully talking butterfly metaphors to William, which created a fortuitous excuse to use some of that footage as a little thematic segue! Later, the fact that Gillian had tweeted that photo (which I think came out around the time I was still editing) and fans were going WTF was that?! - just made me feel all the more reason for keeping it in. I figured hardcore fans would be able to connect the dots without having to really dwell on it too long – and it looks like they did within 2 seconds. It’s odd tiny details like that which you can occasionally sneak in there, and they make me smile. Mystery solved, caterpillar lives another day, everyone wins. :)