Isopod/Woodlouse ID Guide and FAQ for Beginners

[Ghoul]

This is a simple visual guide to identify some of the most commonly found isopod species.

Armadillidium vulgare, common roly poly/pillbug
Armadillidium species in general love to turn themselves into perfect little balls for defense.
http://i.imgur.com/EOsnnCx.jpg
Also come in many colours!
http://i.imgur.com/37h9zel.jpg


Armadillidium nasatum, nosy roly poly
Of course, they also like to turn into little balls for defense.
Their pattern and name giving little squared "nose" tell them apart from other species like vulgare.
http://i.imgur.com/4iC4b4a.jpg
http://i.imgur.com/14g38sg.jpg
http://i.imgur.com/af7cirx.jpg


Porcellio scaber, rough woodlouse
http://i.imgur.com/GWMbfJP.jpg
http://i.imgur.com/EkwaRxW.jpg


Oniscus asellus, shiny woodlouse
http://i.imgur.com/y706jZf.jpg
http://i.imgur.com/fDgFE7O.jpg


Trachelipus rathkii, Rathke's woodlouse
Can be tricky to tell apart at first sight from the top two, but they lack the white border of asellus and always have the light stripes going down on the left and right side of their body, which is even noticeable in the patterned ones if you look closely.
http://i.imgur.com/mXy6cG9.jpg
http://i.imgur.com/8M0Dvmp.jpg
If you are still unsure, turn them around (or put them on a transparent surface and look from below) and see how many lung pairs they got. The lung pairs are the white spots towards their abdomen, for Trachelipus sp. it should look like this:
http://i.imgur.com/Pd0OzIal.jpg
If it has only two lung pairs instead, then it's scaber. If there's no visible ones, it's asellus.

Trachelipus ratzeburgi
If it looks like rathkii, has the same lung count, but has the following colours/pattern, it's probably ratzeburgi.
http://i.imgur.com/PqcNB1S.jpg


Porcellio spinicornis, brickwork woodlouse
Their pattern and the dark head and butt is usually a straight giveaway.
http://i.imgur.com/WObblyO.jpg
Additionally, they have a little spike at the start of their antennas.
http://i.imgur.com/AQ8WHb7l.jpg
http://i.imgur.com/Vo08hGj.jpg
Don't recommend handling them, while they are harmless they are lightning fast when they feel startled.


Porcellio dialatus, grand canyon woodlouse
Looks similar to scaber, but is a lot rounder and bigger.
http://i.imgur.com/YjARnGW.jpg
http://i.imgur.com/84HgaN6.jpg


Porcellio laevis, smooth woodlouse
Smoother than scaber, even it's head shape is smoother. Their heads appear a little smaller than in scaber as well.
http://i.imgur.com/ZLnQYKt.jpg
http://i.imgur.com/QUhCJG1.jpg


Porcellionides pruinosus, powder blue woodlouse/plum woodlouse
Note: If you live in the southwest of the US you may have found Porcellionides floria instead, as they look very similar to pruinosus. http://www.inaturalist.org/guide_taxa/283604
http://i.imgur.com/MRdcY58.jpg
http://i.imgur.com/rI1Gf4G.jpg

Philoscia muscorum, striped woodlouse/moss woodlouse
http://i.imgur.com/XjTpWDE.jpg
http://i.imgur.com/BosWdxy.jpg
http://i.imgur.com/zEdz3cs.jpg
Often seen with a black head, but there are exceptions.
http://i.imgur.com/ydbsJnx.jpg


Hyloniscus riparius
One of two similar species often found near lakes in the mud, and a rather small species.
http://i.imgur.com/qyPzFyj.jpg

Trichoniscus pusillus/provisorius, common pygmy woodlouse
Wait, this one just looks like the one above, doesn't it?
Well, here's some help: http://m.imgur.com/vsOTaJn
http://i.imgur.com/A8DfBQf.jpg


Ligia oceania, sea slater
If you're near the shores and you see a woodlouse chilling there with big eyeballs, it's probably a Ligia species.
http://i.imgur.com/MX8Mo9s.jpg
http://i.imgur.com/KHdeD39.jpg

Disclaimer: Pictures do not belong to me, they are taken off of Google, merely for the purpose of educating people and are not used for commercial use.

 

[Ghoul]

Frequently Asked Questions

Where can I find isopods?
Most species live anywhere where they get food, moisture and darkness. In yards or parks under rocks, wood, in the dirt, in the basement, maybe even your house (which means you probably have an issue with moisture inside your house).
In the forest your best bet is near any dead and rotting wood, carefully check under the bark or lift/turn pieces of wood around to see if there's any isopods hiding underneath. Be careful though, as certain ants and ticks love these places as well.

What do isopods eat?
Any (dead) organic matter, really. They're the garbagemen of nature. They even eat their fallen comrades. If other animals can eat it then isopods should be fine. Avoid citrus fruit or salty things though, as they depend on moisture to breathe. They also eat poop and mold, which makes them a perfect terrarium cleaning crew.

What are the dangers of keeping isopods with other invertebrates?
If your isopods lack something in their diet, they can end up chewing on molting inverts and eachother. If you keep that in check though, the one species I would not recommand in keeping with other inverts is Porcellio scaber, there is a good reason why this species has made it all over the world en masse, and it wasn't for being gentle. Oniscus asellus on the other hand are a rather calm species, and dwarf whites/dwarf purples (found in most online terraristic shops) are often kept as a cleaning crew without issues as well.

I saw an isopod whose body was perfectly half pale, half naturally coloured, what is happening with it?
It's molting! They shed their skin as they grow, which happens in two pieces. That makes them less volunerable than species that shed their entire exoskeleton at once, as they just have to wiggle out of each half and are already prepared to escape predators.

Can different species interbreed?
If they commonly occour together, most likely not. For species of different regions it is unknown. If they share the same genus there is a possibility, but that doesn't mean they can. There hasn't been any recordings of interbreeding in the hobby yet.

What are morphs?
Morphs are colour or pattern variants within a species that can be isolated and bred. Porcellio scaber for example has many morphs, like orange, albino or dalmatian, which are often bred in captivity for their gorgeous looks but can occassionally occour in nature. Common natural morphs for scaber would be grey and calico.

I found a very saturated blue woodlouse, is it a rare morph?
http://i.imgur.com/PXfnvYB.png
Blue/purple isopods are unfortunately victims of the iridovirus, which causes them to appear blue/purple and kills them shortly after.

Can I keep [isopod species x] together with [isopod species y]?
You can, but most species will outcompete eachother for resources (or, often in scabers case, get chewed on). Some are slow breeders and you would end up having 100 of [species x] and 10 of [species y] within a few months, so it is prefered to keep them seperated.

How do you tell males and females apart?
Female on the left, male on the right.
http://i.imgur.com/RUUGhpf.jpg
http://i.imgur.com/POpKdjC.jpg

How do they get babies? Do they lay eggs?
Female isopods have a brood pouch for their eggs/babies, once they are old enough it pops open and the babies come out. It's that big yellow thing on their underside!

Why do they dip their butts into moist surfaces?
They can drink not only with their mouth, but with their butt as well. Isn't nature amazing?

Many of my isopods suddenly disappeared but I can't find any dead bodies, what happened?
They love to burrow, especially when it is too dry or/and too hot, so they are just hiding inside the soil.

~~~

How do I keep isopods?

[Make sure to look into information of the species you are keeping to adjust the set up! Some prefer more moisture while others prefer entirely different environment, and some are sensitive to high temperatures!]

You need:
- a box with a few air holes
- eco earth/soil/earth from outside(preferbly where you found them) (if you go all on coconut fibre you can cause a genocide so please mix it with regular earth at least)
TIP: Bury a banana peel in the soil, they will enjoy that surprise.
- a source of calcium (ground up egg shell or cuttlebone)
- leaf litter
And you're already good to go!
> Now all you need to do is make sure they have enough moisture (the soil should be moist but not soaking wet) and keep an eye on it so it never gets too dry.
> Common snacks for your isopods are cooking leftovers such as veggies or bits of cooked egg, banana, apple, fish flakes, a piece of kibble, a bit of meat, a bit of mushroom... you get the idea. If you keep other critters, dead insects can be a snack for isopods too. Rotting wood and moss is also enjoyed.
> Always make sure they got enough leaf litter and proteins to keep them happy.
> Pieces of cork bark on top of the soil make for great hiding spots, which are also good for checking on your isopods!

 

[Hisserdude]

Very nice, both the identification and care sections are very well written and detailed nicely!

Only thing I have to argue about is that they need a calcium source, I've never given any of my isopod species a calcium source, and they have all done very well in my care, (except for Porcellio silvestrii, my culture almost died out a few months ago, but now they are doing OK.).

 

[spotropaicsav]

Thank you very much for taking the time to post this! I have saved it, also appreciate that you included some US species. I have been looking for a beginners guide such as this! Extra points for the drinking from butts part I think A vulgare still my favorite

 

[Ghoul]

Edit: Argh, it was supposed to say GIANT canyon woodlouse in the ID post, curse autocorrect!

Thank you guys! It took me so many hours, you can't imagine how relieved I was when I finished it. Whew!

Only thing I have to argue about is that they need a calcium source, I've never given any of my isopod species a calcium source, and they have all done very well in my care, (except for Porcellio silvestrii, my culture almost died out a few months ago, but now they are doing OK.).

I can see it not being needed when they get enough calcium through their food already, but since I can't really monitor what type of veggies or such everyone is feeding them I thought it would be better to include that.

 

[spotropaicsav]

Thank you guys! It took me so many hours, you can't imagine how relieved I was when I finished it. Whew!

I can see it not being needed when they get enough calcium through their food already, but since I can't really monitor what type of veggies or such everyone is feeding them I thought it would be better to include that.

Your work was not in vain! I think others will use as well

 

[Hisserdude]

Edit: Argh, it was supposed to say GIANT canyon woodlouse in the ID post, curse autocorrect!

Thank you guys! It took me so many hours, you can't imagine how relieved I was when I finished it. Whew!

I can see it not being needed when they get enough calcium through their food already, but since I can't really monitor what type of veggies or such everyone is feeding them I thought it would be better to include that.

Autocorrect always seems to make more trouble than it's worth LMAO!

Apparently some species get enough calcium just from dead leaves alone, I always make sure to offer all my species dog food or chick feed every week or two though, just to make sure nothing starts cannibalizing. Oniscus asellus in particular seem to turn on each other rapidly when such supplemental foods aren't offered often, or when they don't have a lot of space.

 

[LawnShrimp]

Now all we need is a picture of every morph and cultivar!
I am currently breeding orange A. nasatum and your care guide matches how I've been keeping them. I caught 9-10 orange ones at two different locations and have about 30 orange babies and 20 greys.

As for morphs, take a look at this pod vendor:
http://captiveisopoda.tictail.com/
Not sure who this guy is but what an amazing collection of morphs and species.

I hope your careguide can help a whole bunch of people!

 

[Ghoul]

Thank you! Yeah I've seen this guys page before as well.

Now all we need is a picture of every morph and cultivar!

If I did that I wouldn't be done in 20 years!
New morphs keep popping up and new species get introduced into the hobby as we speak! I attemped to make a list of scaber morphs and this species alone has a mad amount of morphs.
The variety in colours and patterns in isopods is just absolutely insane, which is one of the reasons why I love them

Autocorrect always seems to make more trouble than it's worth LMAO!

Apparently some species get enough calcium just from dead leaves alone, I always make sure to offer all my species dog food or chick feed every week or two though, just to make sure nothing starts cannibalizing. Oniscus asellus in particular seem to turn on each other rapidly when such supplemental foods aren't offered often, or when they don't have a lot of space.

I have that issue more with scaber than I do with asellus. They will eat their own babies alive when they feel like it, I've been spoiling them but they're still savages

 

[Redmont]

This needs to be a sticky, before it slowly fades off in to obscurity

 

[RTTB]

Very informative. Great article.

 

[Ratmosphere]

Very informative thread, thank you for this!

 

[mickiem]

Glad I ran across this! Great info, thanks.

@davehuth thought you might like this

 

[davehuth]

Glad I ran across this! Great info, thanks.

@davehuth thought you might like this

Thank you @mickiem this is solid gold!

 

[Mirandarachnid]

Thank you for taking the time to put this together!