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Petrolisthes armatus? - Petrolisthes armatus

Petrolisthes armatus? - Petrolisthes armatus
Galveston County, Texas, USA
May 25, 2014
Size: 12mm
I noticed Bugguide did not have images this common invasive species of crustacean.
Found in "tide pools" near seawall, consisting of concrete rocks piled on a concrete slab base. Sargassum was particularly heavy, covering every part of the beach at least a foot deep.

Moved from ID Request.

Thanks for the addition!

Population density is very high in the gulf states!
Thanks for pointing this out! Just read that there can be 30,000 of these crustaceans per square meter in some locals. That would seem likely to have some impact on the local ecosystems!

That's what I read too
Luckily, where I was, the population was not nearly that high, only a few every couple square meters. Still pretty common, though.

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