Lawn Shrimp

Bug identification please
Location: Berkeley, CA
December 19, 2010 8:36 pm
Found these in our finished basement, which is connected by a doorway to an unfinished basement. The dog also goes in there, so stuff from outdoors tends to get dragged in more than in the rest of the house. Area is generally cool, somewhat high humidity. Photos are the same positions, just lit differently. THANKS!
Signature: Earthman

Lawn Shrimp

Dear Earthman,
We suspect that with Southern California experiencing the worst storm in the decade, with predictions being in excess of 8 inches of rainfall in less than a week, your letter will be the first of many requesting the identification of Lawn Shrimp,
Arcitalitrus sylvaticus, though we also predict that your photo will be among the best we receive.  Lawn Shrimp are terrestrial amphipods that proliferate in the damp conditions of well watered gardens, however, when soaking rains arrive, they often seek shelter indoors where they promptly die and turn pink.  According to BugGuide, they are found in : “Moist soil and organic matter within 13 mm of the surface, often among ivy or other groun covers. 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.”   BugGuide also remarks:  “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 dieing 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.”  Lawn Shrimp, which are also known as Househoppers, are not native to California.  They were introduced from Australia.

Hey, thanks so much for the help. Very informative, and your expert reply is much appreciated. You’re doing a public service. THANKS!

5 thoughts on “Lawn Shrimp”

  1. We have these “Lawn Shrimp” in Texas as well !! I never knew what they were until I looked them up on your website !!

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  2. Well I have been seeing these in my yard lately I’m from baxley and I never knew what they where till I just look them up it’s been raining a lot here the last few weeks is that why they’re around

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  3. I just found two of these “lawn shrimps” at the doorsteps at home in Sao Paulo, Brasil. I’m 60, and have NEVER seen these bugs in my life. And let me tell you, I have 15 “micos”( little monkeys) visiting almost every day here,( have no idea where they come from, but they use the green corridors in the city) so I’ve seen a lot of “wild life” in my garden!? But shrimps was a first!? What do they eat? Are they harmful to the garden/lawn in any way? It has been raining a lot here and it’s insanely hot also! Thank you for this page! My son in law found it and showed me.

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    • According to BugGuide, their food preference is “Dead organic matter in the soil, especially eucalyptus” and “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.

      Reply

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