Mantis shrimp are not quite a cosmopolitan species, but they are very close. They normally live in the warm waters of the Pacific or the Indian Ocean. They are primarily found between Africa and Hawaii, but not all of the species are found within this range. Afterall, there are 450 different species of mantis shrimp, so their realized niche is in tropical and subtropical oceans worldwide.
Mantis shrimp typically like to live in sandy areas, as they like to dig elaborate tunnels as their homes. When they are not hunting, they are always in their tunnels. They are known to be very territorial creatures and show aggression to intruders.
A study done off the coast of Costa Rica found 50% of the species Squilla biformis found lived at a depth of 250 meters, but they were found as deep as 350 meters. They sampled 1778 shrimp in this study. They were unable to find the largest size of these individuals, and hypothesized that they were able to reach depths that fishing vessels could not.
Biological Brilliance 