Two days ago I stumbled out of bed onto a scene of ...what? Not horrific destruction or even horror, but onto something that definitely piqued my curiosity.

There were a dozen or so "things" lying on the dining room carpet that at first looked similar to some tree detritus that the dog tracks in from the deck, but on closer inspection turned out to be, ummm, not sure if they are eggs, pupae, cocoons, chrysalae (is that the correct plural of chrysalis? For lack of a better term I'll refer to them as pupae) or what, each about a quarter inch long. How did they come to be there, I wondered? Then I moved an empty cardboard box that I had been intending for the last 10 days or so to haul downstairs to the trash area, and there were another 60 or 80 of the things underneath where the box had been resting. This further piqued my curiosity, and started ringing alarm bells of concern in my previously tranquil mind.

So I started moving other things -- things like cloth tote bags full of files from my scanning project that weighed 25-30 pounds apiece -- and underneath everything I moved there were more of them. All in all, I would estimate between 200--300 in total.

Then I noticed that they were starting to hatch. Just starting. I spied a tiny yellow caterpillar inching it's way across the rug, then another, and another. Concern, which had replaced tranquility a few minutes earlier, now started giving way to panic. I grabbed my weapon of choice (Mr. Dyson) and sucked them up caterpillars and all, got out the crevice tool and worked over the junction between carpet and wall, and then sprayed insecticide into the input hose for good measure.

Deciding that this was getting serious, I then moved everything out of the dining room, table, chairs, the rest of the tote bags, a picnic cooler that was stuck in a corner, just, you know... stuff. And under everything were more pupae. Then I saw a fourth caterpillar trying to escape across the linoleum floor in the kitchen. "Not on my watch, you multi-segmented intruder into the sanctity of my domicile!" I cried (or more likely something along the lines of "Aaarrrgggh!") and without regard for my personal safety, knowing that it was a matter of do or die, I switched on my weapon which responded with a loud "harrroooo" and fearlessly advanced on the offending infiltrator.

He offered surprisingly little resistance.

Then I started moving things in the kitchen. More pupae under the bathroom scale (yeah, we keep it in the kitchen, it encourages portion control), under the dog's food dish, in the toe spaces under the cabinets. Not so many in the kitchen, I think because it was further away from Ground Zero which was apparently the empty cardboard box, and maybe because there was no carpet to hide in.

After that, I vacuumed the kitchen floor, then mopped it. Then I re-vacuumed the dining room, and took the crevice tool and meticulously explored with considerable suction every possible crevice I could find. I then did a more cursory vacuuming of the remainder of the house where I had seen no signs of infestation.

Two days later there are no signs of pupae or caterpillars.

So, now the questions.

The empty box came from China by way of Costco, it had contained a large roll-along duffel bag/suitcase for SWMBO. I wonder if the original egg-layer came from this box?

It would appear that whatever laid the eggs was small enough to crawl through carpet fibers that were compressed beneath some pretty heavy objects. This seems unlikely, given the size of the pupae. There were no pupae under the table, which weighs about 70 pounds and rests on a 24" diameter pedestal. [Warning! Math Alert!] That would be 12*12*3.14 or about 450 square inches, for a loading of .15 pounds per square inch. The tote bag full of files weighed 28 pounds and, was 12" x 12" or 144 square inches, for a loading of .19 pounds per square inch. [End Math]. Could it be that whatever it was could burrow under .15 pounds loading but not .19 pounds?

Here's another possibility. Two weeks ago I shampooed the carpets. Being a lazy git, I did not move the dining room table, figuring that the carpet beneath that pedestal had been covered for the last two years and didn't need shampooing, plus I had doubts about how well the carpet would dry being covered by a solid two foot wooden disk weighing 70 pounds. Could the eggs have been hibernating in the carpet and been triggered by the moisture of the shampooer? Naaahh, not likely, that wouldn't explain the pupae beneath the scale and the dog dish in the kitchen.

How could these pupae appear literally overnight? I know that the ones hidden under stuff could have been there for a while, but there were a bunch that just showed up out in the middle of the floor. I don't know a lot about insectile reproduction, but it seems to me that something capable of producing that many sizeable pupae in one session would have to be pretty big, far too large to burrow through carpet fibers under a 28 pound tote bag, yet something small enough to do that would have to produce very tiny eggs that could not grow to the size of those pupae without considerable nourishment.

Can anyone offer an explanation of what went on here? Do you think it likely that my infestation is over? Should the Board of Health condemn and raze the entire housing complex?

What, if any, future action should I contemplate?

tanstaafl.

Are your carpets wool?

http://www.ext.colostate.edu/PUBS/INSECT/05599.html

-jk

No.

To test this I touched a carpet fiber to a hot electric stove element. It melted rather than smoking and/or burning.

tanstaafl.

ech!
What a way to wake up!

Well- a quick googling for 'bug eggs in carpet' yielded lots of results, but the first few hits didn't give me any pictures like yours.

If I were you, I'd be tearing apart the bed and closets, too.
It seems the common 'carpet beetle' eats natural fibers.

This page has a thing that looks like yours, #385:

http://pestcontrolcanada.com/Questions/pest_photos_301_t.htm

"This appears to be a puparium of a higher muscoid fly (Diptera; suborder Cyclorrhapha), a very large group that includes the common house fly ... When the maggots are mature, they usually wriggle away from the food source in search of a drier place in which to pupate,"

So it would seem the maggots have moved AWAY from somewhere and not necessarily anywhere near where you saw most of them, that might have just been the most appealing place. Any old food left around there?

"Chrysalides," from the Greek. Not a pluralization you hear in English often, if ever. The only other example I can think of is "irides" as the plural of "iris". The notionally correct plural of "octopus" is "octopodes", which I suppose might be formed from the same rule ("<vowel>s" → "<vowel>des"), but I'm hardly a Greek scholar. It seems that most Greek loanwords of this form have been loaned as plurals and back-constructed to singulars: "antipodes" → "antipode" (instead of "antipus"), for example.

I believe you nailed it.

I didn't understand the sequence... I thought that what I was looking at were the "eggs" and the "caterpillars" were the results. Instead, the "caterpillars" had grown from tiny eggs, and were turning into the brown pupae, after which they would have metamorphosed and flown away.

And yes, there was a food source -- for the past few days there had been a plastic bag full of kitchen trash, carefully tied off (but obviously not tied well enough!) stuffed into the box.

At least now I know that if I missed a few of the pupae (inevitable, I think) the worst that will happen is that in a few days they will fly away.

The depth of knowledge and ability to research that is evident on this bbs never fails to amaze me.

tanstaafl.

Except that before flying away they will leave another generation.

And Yes, flies can do has you have experienced. Once or twice I've found, in the AM, a large spread of white maggots, racing away from the trash bag across the kitchen floor. (in so much as maggots can be seen to race)