The moor is cold and still. From the bleak tors topped with lumps of granite creased like fossilised dough to rocky valleys and bristling slopes of gorse, it waits for spring sunshine to warm its bony back. Save for a few birds animating the frostbitten hedgerows, my garden on the western flank of Dartmoor stares back at me blankly. Yet there is life to be found, taking refuge under plant pots on the veranda.
Beneath every lifted pot is a disc of dampness, dark as a vinyl record stencilled on to the flagstone. And sheltering within each moist circle, an assortment of invertebrates: slugs plump as black olives, centipedes, beetles, earwigs. Most are slow to react, skulking off bleary-eyed in search of cover. But a species among them, similar to a large flea, rapidly pings away the moment it is exposed to sunlight.
I manage to catch one of these leaping commas for a closer look. Roughly a centimetre in length, its segmented body resembles that of a woodlouse – only flattened vertically rather than horizontally, as if it had squeezed through a closing door. Its curled tail end and long rear legs are primed to propel it from danger. However, this is no blood-sucking flea but a secretive and less familiar invertebrate that feeds on leaf litter and organic detritus – a landhopper.
Closely related to coastal sandhoppers found under stranded tideline seaweed, the landhopper (Arcitalitrus dorrieni) is an inland crustacean, also going by the name lawn shrimp.
Rather aptly, this little jumper hails from the land of kangaroos. Native to Australia, landhoppers were first recorded in Britain a century ago on the Isles of Scilly, having arrived as stowaways with imported plants. They have spread widely, though are most common in the south and west. While these arthropods can crawl and jump many times their length, they hitch a ride over longer distances in the soil of potted plants – which is, presumably, how they came to be living in my Dartmoor garden.
Lift a pot, log or stone, even on a winter’s day, and one can spot them popping and scattering from the flat cold ground as if it were a hotplate. A curious burst of life at this sluggish time of year.
Under the Changing Skies: The Best of the Guardian’s Country Diary, 2018-2024 is published by Guardian Faber; order at guardianbookshop.com and get a 15% discount
