The Defra Code of Practice also contains advice and information on where to send flatworms for identification

The sites represent premises, which have received confirmation of the presence of the NZ flatworm, in the Defra-commissioned survey carried out by ADAS. In practice, most suspect flatworms sent to the ADAS Plant Clinic, turn out not to be A. triangulatus, but rather comprise other invertebrates, including slugs, worms and leeches, as well as other flatworms (both indigenous and non-indigenous). In particular, the large carnivorous leech, Trocheta subviridis, itself an earthworm predator, is frequently mistaken for A. triangulatus.

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Locations in England and Wales with confirmed records of the New Zealand flatworm, Arthurdendyus triangulatus. As of 29 March 2006.