Obama Flatworm

Fast Facts

Latin name: Obama nungara

Notable feature: Invasive Non-Native Species (INNS) in the UK

Conservation Status: Not Evaluated

Where in the UK: This Invasive Non-Native Species (INNS) is found across the UK in scattered populations

Obama Flatworm (Obama nungara) © M.Izumi


The Obama Flatworm (Obama nungara) is a non-native species, originating from Brazil and Argentina; it is considered invasive as it is spreading rapidly and its presence is impacting our native wildlife here in the UK.

The Obama Flatworm has a broad, leaf-shaped ordinarily dark brown body, with numerous black streaks along its back.  Colour can vary from very dark to mid-brown with some Obama Flatworms having a pale midline and pale underside.  This flatworm can measure up to 10cm in length and about 1cm wide.

The Obama Flatworm has hundreds of eyes distributed along its body.

This flatworm was recorded in Guernsey in 2008 but wasn’t identified until 2016; since this time it has made its way across the water to the UK.

    • Size: 10cm in length
    • Life span: Undetermined
    • Diet: The Obama Flatworm feeds on earthworms (such as the Lob Worm aka Common Earthworm), snails and other flatworms.
    • Reproduction: Reproduces by laying black cocoons about 5mm in diameter; several hatchlings emerge after a few weeks.
    • When to see: Found year round in dark, damp situations such as in soil, leaf litter, at the bases of plants, or under logs, stones, plant pots and other objects.
    • Population Trend:  Increasing numbers of reports across the UK
    • Threats: There are no recorded natural enemies and no biological or pesticide control methods for non-native flatworms, the key control measure is to prevent their introduction to new areas.
    • Fun Fact: Oba ma means ’Leaf animal’ in Brazil’s indigenous Tupi language
    • Bonus (not so) Fun Fact: Obama Flatworms are considered extremely invasive; deemed one of the most threatening flatworm species to the soil ecosystem and native soil organisms presently in Europe.

As with other flatworm species the Obama Flatworm is likely to be distributed via the movement of plants and growing media in the horticultural trade.

How you can help: 

Buglife is working to increase awareness of Invasive Non-Native Species (INNS) and their, often detrimental, impacts on our native wildlife and habits.  Working with other organisations to highlight how biosecurity is everyone’s responsibility and that we can all play our part.

Join a recording scheme and log your flatworm finds – send any records/sightings to our flatworm recording scheme – Potwatch!

Follow our biosecurity guidance (at the bottom of the linked page) on flatworms to help prevent their spread and destroy any non-native flatworms that you find.

Do remember that we rely on donations to continue our work.  If you have searched, found and learnt about our incredible invertebrates on our website, please do consider Making a Donation, Becoming a Member or maybe even making a purchase in our shop.  For more ideas on how to support our work find out how to Get Involved.  Thank you 🕷