Wood lice = Pill bugs?

Wolvie56X

Arachnobaron
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not sure if this has been covered, but i was looking up info on the small red centipedes in ct and wood lice came up, pets section, and they look like pill bugs to me
 

J Morningstar

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I am sorry Pillbugs are pill millipedes, sowbugs and woodlice are isopod crustations. Pillbugs can roll into a ball woodlice cannot. They are not the same. Centipedes will eat Pillbugs, they will not eat sowbugs. Rollipollies are pillbugs.
There is a great deal of physical and anotomical differences. Isopods have gills. This has been covered before in the posts.
J
 

Elytra and Antenna

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J Morningstar said:
I am sorry Pillbugs are pill millipedes, sowbugs and woodlice are isopod crustations. Pillbugs can roll into a ball woodlice cannot. They are not the same. Centipedes will eat Pillbugs, they will not eat sowbugs. Rollipollies are pillbugs.
J
Pillbugs are not pill millipedes. They are as close to each other as to a tarantula.

I have fed many sowbugs to Scolopendra and Alipes centipedes.

If you check with the ESA (Entomological society of America) or ATS (American Tarantula Society) you'll find the common name for terrestrial isopods are either pillbugs or sowbugs. Both groups are isopods and are crustaceans in the malacostraca along with shrimp, crabs, etc.

Woodlice, rollipollies, rockbugs, little gray critters, etc. are 'incorrect' common names for members of the order isopoda. This is not my opinion. Contact the ESA or ATS with common name questions.

DarkRAM is pretty much dead on.
Pillbugs and sowbugs are the names for two different groups in the order isopoda. The only fuzzy part is that not all pillbugs can roll into a ball and some sowbugs can.
 

J Morningstar

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MantidAssassins]Pillbugs are not pill millipedes. They are as close to each other as to a tarantula.
Pillbug, in common usage referes to things like Giant Green Madagascar Pillbug or Tanzanian Tan Pillbug both of which are Pill Millipedes.

I have fed many sowbugs to Scolopendra and Alipes centipedes.
I had a isopod live with both my centepede happily for years with never a incedent, the pill millipedes were consumed on the other hand.

If you check with the ESA (Entomological society of America) or ATS (American Tarantula Society) you'll find the common name for terrestrial isopods are either pillbugs or sowbugs. Both groups are isopods and are crustaceans in the malacostraca along with shrimp, crabs, etc.
I remember from the last debate that this is an incorrect common name usage thing. Different parts of the world refer to them as different things. But it only makes sense that "Pillbug" would refer to some thing that could become a ball or pill shape like a pill millipede where the sowbug isopod cannot (at least none in the NE United States can).

Woodlice, rollipollies, rockbugs, little gray critters, etc. are 'incorrect' common names for members of the order isopoda. This is not my opinion. Contact the ESA or ATS with common name questions
.

You're right they are common usage errors for things people see as little grey things. Rollipollie would again refer tho some thing that became a ball, a pill millipede.

DarkRAM is pretty much dead on.
If he can find a picture of an isopod in a ball sealed shut like a closed pill millipede. Again I think the people who make identifications some times use the improper common name out of geographic habit.

Pillbugs and sowbugs are the names for two different groups in the order isopoda. The only fuzzy part is that not all pillbugs can roll into a ball and some sowbugs can.
IME I have NEVER seen a pill millipede that could not became a ball (though I am sure that a few may not). I have also never seen any photo of any isopod that could even come close to becoming a ball. This is just weird that the regional difference would create such a debate.
 

Elytra and Antenna

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The African and Malaysian millipedes are millipedes, not isopods.
The animals you fed to your cenipedes were isopods, not millipedes. There are no pill millipedes in NJ.
Your confusion (of course it's not your fault since someone on arachnoboards started calling them pillbugs accidentally and everyone here followed suit) of the names leads you to believe that if it rolls into a ball it is in the same group. Pillbugs, pill millipedes and pill cockroaches (and armadillos for that matter) are very different groups that have convergently evolved the same method of defense. Upon a close look it is easy to see they are extremely different groups. The next time you find your pillbug outdoors, unroll it and look closely, there are 7 leg pairs (no more than one per segment) and the body ends in a distinct abdomen which possesses no walking legs (there are two appendages at the end of the abdomen as on all isopods).
Many isopod species roll into balls just like pill millipedes, so do a few roach species.
Names for species that can roll into a ball:
Isopods = pillbugs
millipedes = pill millipedes
cocroaches = pill cockroaches

I am trying to help, you are welcome to call them all scorpions or beetles. If you plan to answer, please check any book containing information on isopods.
 

Pedro

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Pillbugs and sowbugs though similar are different bugs. Sowbugs and pillbugs are crustaceans and are closely related to crayfish and shrimp, more so than to insects.

Often confused with sowbugs, one of the distinct differences of sowbugs and pillbugs is that a pillbug has the ability to roll its body up into a ball resembling a small pill; a sowbug does not roll into a ball.
 
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Scorpiove

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Pedro said:
Pillbugs and sowbugs though similar are different bugs. Sowbugs and pillbugs are crustaceans and are closely related to crayfish and shrimp, more so than to insects.

Often confused with sowbugs, one of the distinct differences of sowbugs and pillbugs is that a pillbug has the ability to roll its body up into a ball resembling a small pill; a sowbug does not roll into a ball.
Besides....... lobster, shrimp and crayfish are bugs too. :p
Not insects though.
 

DarkRAM

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J Morningstar said:
If he can find a picture of an isopod in a ball sealed shut like a closed pill millipede. Again I think the people who make identifications some times use the improper common name out of geographic habit.
Well, its not completely closed in the pic. I had to dig it out and by the time I grabbed the camera & focused it started to open up.
http://darkram4.com/ipw-web/gallery/albums/album29/Bugs_5.jpg
Here is it open:
http://darkram4.com/ipw-web/gallery/albums/album29/Bugs_3_001.jpg

If I managed to snap a pic of it completely closed I'll post it here.
 
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