New Zealand flatworms

Time to act:

Jun, Jul, Aug, Mar, Apr, May, Dec, Jan, Feb, Sep, Oct, Nov

The New Zealand flatworm was first introduced to the UK in the 1960s, although it has never become as great a problem as was originally feared. It's purple-brown on top, and flat and pointed at both ends. When resting it coils up, is covered in mucus, and is about 1cm wide by 6cm long, although when extended it can be up to 30cm long. It lives on earthworms, covering them in digestive juices to dissolve them before sucking them up. The larvae of ground beetles prey on flatworms.

Researchers are eager to know of new sightings. Should you discover a possible flatworm in your garden, please take a digital photograph and email it to When taking photos, place an object such as a pencil, or a key, alongside the creature to provide scale.


The numbers of our native earthworm are declining thanks to this invasive worm - it loves to feast on them.

Find it on

undisturbed ground, under stones, logs and pots. Prefers cool, damp habitats.



Check sites where they like to hide undisturbed - for example under stones and pots - and dispose of any you find. Where there's one, invariably you'll find more. Where they are present, spread a sack on the ground, weigh it down and keep checking if more are hiding beneath. Eggs are usually found between June and September. Destroy the worms by squashing or dropping them into salty water.


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