At Swell Reptiles, we offer two different kinds of Earthworm:
The "Small Worms" that we sell of a species called Dendrobaena. Noted for being extra wriggly, they are great for unenthusiastic larger reptiles - the extra movement perks their interest in the food, making them more likely to tuck-in sooner, rather than later.
Although considered small, Dendrobaena worms can be up to 50-75mm long, meaning that they're best for larger reptiles such as blue tongue skinks or tegus. Some amphibians, such as salamanders, are also fans of these juicy treats.
Our larger Lumbricus worms are often called Giant Lob Worms, and look similar to the worms found in gardens all over Europe, but with one essential and all-important difference - they are captive bred which means they are free from the diseases and parasites that commonly infest worms found in the wild. You should never feed wild insects to your reptiles for this very reason: whatever the worms are carrying will end up in your poor reptile! Instead, use this page as a good, cheap source of tasty earthworms for your reptile, at a fraction of the likely vet bills caused by wild-feeding.
These little guys can outlive many other types of reptile live-food, living much longer than crickets or locusts for example. All they need in order to thrive is soil, making them very easy to keep.
Earthworms are a great treat but not necessarily a long term food, any leftovers needn't go to waste as they can work wonders if thrown on the compost heap or can even be used as fishing tackle for keen fishermen.