Entomology (Study of Bugs)/Bug


"Moving" Shell
"Moving" Shell  

"Live" shell
"Live" shell  
Moved to a new wooden house in the western suburbs of Sydney nsw australia. I noticed these little things hanging the ceiling in the bedrooms "like a bat". Looks like a shell, a rice grain but flat. Does not look alive. This was end of August 2014.
I just vaccummed them.
Few days after, I found one in my bathroom towel.
And one was "climbing" the wall towards the ceiling in the bathroom.
This is when I realised it is moving.
The day after I had one on my pillow.
And today, the 1st of October, one was in the bathroom sink, and a little and very thin "worm" was coming out of the shell. I have attached 2 pictures. Let me know if you require more info or photos.

Hi, Pascale:

Even though you are writing from Australia, I believe the organism in question is found almost globally.  Thank you for including the images with your question, by the way.

I am pretty sure these are the "Household Casebearer," a type of moth caterpillar.  More about them here:


The species was formerly known as the "Plaster Bagworm."  Apparently they feed mostly on abandoned spider webs, so as scavengers they are at most a nuisance, not a real pest.

Hope this helps!  It is certainly a member of the same family as the Household Casebearer, if it is not that exact species.


Entomology (Study of Bugs)

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Eric R. Eaton


I answer insect and spider identification questions ONLY. Attach images if possible. No "what bit me?", "what do I feed this bug in captivity?", or science fair project questions please. NO TECHNICAL QUESTIONS ABOUT INSECT PHYSIOLOGY.


Principal author, Kaufman Field Guide to Insects of North America. Professional entomologist employed previously at University of Massachusetts, Chase Studio, Inc., and Cincinnati Zoo; contract work for West Virginia Department of Natural Resources, Smithsonian Institution, and Portland (Oregon) State University.

Author, Kaufman Field Guide to Insects of North America, Missouri Conservationist magazine, Ranger Rick, Birds & Blooms, Timeline (journal of the Ohio Historical Society). I have contributed to several books as well.

Oregon State University, undergraduate major in entomology, did not receive degree.

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One of the top 50 experts in all categories for AllExperts.com, 2009.

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Principal author of the Kaufman Field Guide to Insects of North America, Smithsonian Institution (contract), Cincinnati Zoo (employer), Portland State University (contract), Chase Studio, Inc (employer), Arkansas Museum of Discovery (guest speaker). Currently seeking speaking engagements, leadership roles at nature festivals, workshops, and ecotours.

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