Species Arcitalitrus sylvaticus - Lawn Shrimp

Landhopper

First described by William Aitcheson Haswell in 1880 as Talitrus sylvaticus

The genus Arcitalitrus was later split off with this as the type species.

Latin: a variant spelling of silvaticus- "of or belonging to woods" from silva- "woods"

8 mm

Shrimp-like creatures with many legs that can hop like fleas. Springtails are much smaller and have only 3 pairs of legs

Southeastern Australia (New South Wales and Victoria), as well as nearby areas of the Pacific, but introduced into New Zealand, the British Isles, Florida and California

Moist soil and organic matter within 13 mm of the surface, often among ivy or other ground covers, mostly eucalyptus. Their exoskelton has no waxy coating to keep moisture in, so they can't survive dryness. They drown in water, though, so they need continuously moist, but not waterlogged conditions.

Year-round, but most visible when weather is either too dry (they leave their habitat search of moisture) or too wet (they leave flooded soil to keep from drowning).

Dead organic matter in the soil, especially eucalyptus.

The female lays her eggs after mating in a pouch on the underside of her body. The babies are like smaller versions of the adults, and leave the pouch soon after hatching.

These are rarely seen except when flooding or lack of moisture forces them to abandon their home in the soil in search for suitable conditions. At such times they often end up dieing on pavement or in homes and become a nuisance. Once they start appearing, there's not much that can be done except to sweep them up- pesticides are pointless, bcause by then they're already dying or dead.

The best solution is to keep the numbers down the rest of the year by keeping the soil from staying too moist- in California, especially, they're a sign of overwatering. Physical barriers like weather-stripping can also help to keep them out of homes, but their bodies are flat and narrow, allowing them to slip through surprisingly narrow cracks.

Non-native; introduced probably from Australia along with blue-gum eucalyptus trees in the 1800s. First recorded in San Francisco, CA in 1967

Featured Creatures: an article on terrestrial amphipods of Florida.

Journal of Crustacean Biology

Proceedings of the Linnean Society of New South Wales, v.4, p.246    Haswell's original description of the species.