The landhopper Arcitalitrus dorrieni (a terrestrial amphipod that looks similar to the common sandhopper you see around the strandline on the beach) was originally described from the gardens of Tresco on the Isles of Scilly in the mid-1920s, where it was regarded as an immigrant from Australia. It's likely that the landhopper probably uses potted plants as its main mode of dispersal.
It was first shown to me in 1995 by Paul Llewellyn in Caswell Valley, where it was superabundant under the Holm Oaks adjacent to the car park. We found it to be less abundant, but widespread throughout much of the woodland there and so was clearly well-established. In recent times I have heard of more records e.g.
Ian Morgan first saw the species under Cherry Laurel leaf litter at Furnace, Llanelli in 1999, and subsequently in Denham Avenue, Llanelli 2002-2010, Llwynhendy 2009 and at his current address Pwll in 2010. All vc44, Carms.
Graham Motley wrote that it occurred at ‘Bracken Road, Neath (behind the cricket and rugby grounds) from 1994 to 1997. I remember numbers being much lower though in the summer of 1997 - presumably they suffered due to the prolonged very cold spell in January of that year.’
The map below shows the records I have collated to date (updated with additional records 01-Dec-10. Thanks to contributors):
If you have seen this species, especially from any new sites, please share your sighting here and/or contact:
Dr Michael R. Wilson
Head of Entomology Section
Department of Biodiversity & Systematic Biology
National Museum of Wales
Cardiff, CF10 3NP, UK firstname.lastname@example.org