Greg Laden's Blog has a fascinating film about the truly amazing speed that these 'shrimps' move, which is quite unbelievable - they would have put Mohammed Ali in the shade.
It's a fascinating film. We have 'amimintiks' here in the Philippines - they're the spearing species shown in the film. They are extremely fast, and their grabbing arms are lined with needle-sharp spines - very sharp - you can't even handle one without getting pricked.
When you're snorkelling, you can hear them underwater - sharp reports from time to time - not all their efforts result in anything very much.
I featured them in a tale about Sunday afternoon reef foraging (right at the end):
and I can confirm that they are very tasty indeed - like lobsters but at 1/10the price. Here, they catch the spearers with sprung nooses set just above their sand holes. A bit of springy bamboo, a bit of string, and some fishy bait is all that is needed.
At some time in each month, some of them come loaded with 'coral' - eggs, that are the most tasty part. But, unlike lobsters, crabs, etc, that grow their eggs under their bellies, amimintiks grow theirs under the shell of their backs, so they have to moult to give birth.
There's a small local estuary here that no-one will dare cross, because although it is shallow enough, it is full of amimintiks, and they've been known to kill carabaos - the local domesticated water buffalo.
In the two photos above, you can see the creature in full size (about 10" long), and the truly awful structure of its grabbing claws.
But they are very tasty