Why Are Isopods Called Woodlice?
Isopods are commonly known by several different names depending on where you live. In the UK they are often called woodlice, while in other countries they may be known as pill bugs, roly-polies, or sowbugs.
The name woodlouse can sound misleading, especially because isopods are not actually lice. In reality, they are crustaceans — much more closely related to shrimp and crabs than insects.
If you're looking to buy isopods in the UK, understanding what woodlice actually are will help you choose the right species and build a suitable enclosure. For full guidance, see our isopod care guide and isopod species guide.
The name developed simply because these animals are most often found living in damp wood, leaf litter, and decomposing material on the forest floor.
The Meaning Behind the Name Woodlouse
The term woodlouse comes from two parts:
- Wood – referring to rotting logs, bark, and woodland habitats
- Louse – an old English word once used for small crawling creatures
Historically, “louse” wasn’t limited to parasites — it was a general term for tiny animals seen crawling in natural environments.
To understand their true classification, see are isopods insects or crustaceans .
Why Woodlice Live in Wood and Leaf Litter
Woodlice are strongly tied to damp environments because of their crustacean ancestry. Even though they live on land, they still rely on moisture to breathe properly.
In nature, they are most commonly found under:
- Rotting logs and bark
- Thick leaf litter layers
- Stones and shaded ground
- Moss and decomposing wood
In captivity, recreating this environment is essential. A proper setup should include:
- leaf litter for feeding and cover
- cork bark for shelter zones
These materials help create natural habitat zones that support long-term colony stability. You can explore everything needed in our isopod supplies collection.
Woodlice Are Actually Crustaceans
Despite the name, woodlice are not insects. They belong to the crustacean group, alongside crabs, shrimp, and lobsters.
They are one of the few crustaceans that successfully adapted to life on land, evolving behaviours that allow them to survive in soil and woodland environments.
If you want a deeper explanation, read how isopods survive on land .
Different Types of Woodlice
There are many different species of woodlice, and they vary widely in behaviour and appearance.
- Armadillidium: hardy species that roll into a ball and tolerate slightly drier conditions
- Porcellio: fast-moving, active surface roamers that benefit from airflow
- Oniscus: common rough woodlice found in the UK
These behavioural differences influence enclosure design. Some species require more humidity and burrowing depth, while others prefer open surface areas.
You can explore these groups and more in our isopods available in the UK.
Why Woodlice Are Important in Nature
Woodlice are key decomposers in natural ecosystems. They break down dead plant material and recycle nutrients back into the soil.
This is the same role they perform in captivity, which is why they are widely used in bioactive setups.
To learn more, read why isopods are important in bioactive setups .
Why the Name Still Exists Today
Even though science now classifies them as crustaceans, the name woodlouse has remained in everyday language because of its long history.
It’s simple, recognisable, and still reflects where these animals are most commonly found.
Final Thoughts
Isopods are called woodlice because they are typically found living in wood, leaf litter, and damp environments. The name reflects their habitat rather than their biological classification.
Despite the name, they are not lice or insects — they are specialised land-dwelling crustaceans with an important ecological role.
If you're looking for isopods for sale UK or want to browse isopods available in the UK, explore our full isopod collection and build a setup that mimics their natural woodland habitat.
