Periclimenes harringtoni
A rare little find on Grand Cayman reefs, best spotted with a sharp eye and a torch in water around 25 to 31C year-round.
A tiny, mostly translucent shrimp that relies on near-invisibility rather than bold pattern, so divers usually spot it by movement or by scanning coral crevices with a torch. Look for faint speckling and thin, glassy legs against the coral surface rather than any strong colour block. Size in the water is small enough that most divers miss it entirely unless they are hunting macro subjects.
Divers usually find it tucked into coral structure, holding still and blending into the substrate rather than swimming out in the open. It shows little reaction to divers, most likely because its main defence is staying unnoticed rather than fleeing. Most logs describe single individuals rather than groups, so a sighting tends to be a solo, close-focus find on a slow, methodical dive.
Its near-transparent body is a camouflage strategy rather than a lack of colour, letting it sit exposed on coral without standing out to predators or passing divers.
Sightings show no clear seasonal pattern, and with observed water temperatures running from 25.2 to 31.2C, Grand Cayman stays within its comfort range all year, so it is a year-round possibility rather than a seasonal target.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
Grand Cayman in the Cayman Islands is the only place this shrimp is reliably logged by divers, making it effectively a Cayman speciality rather than a wide-ranging find. Within Grand Cayman it turns up across a spread of sites, though never in numbers, so it rewards divers who search rather than swim past.
Mapping where Bermuda Shrimp is logged…
Grand Cayman in the Cayman Islands is the main place divers log this shrimp, spread thinly across a number of sites rather than concentrated at one spot. It has not been reliably recorded elsewhere.
There is no detected seasonal pattern, and Grand Cayman's water stays within this shrimp's comfortable 25 to 31C range year-round, so any month is fair game.
Look for a small, mostly translucent shrimp with faint speckling and glassy legs, sitting still against coral rather than swimming in open water. It is easy to miss without a slow, close look.
Exact size data is not well documented, but like most Periclimenes shrimp it stays small, typically only a centimetre or two, making it a macro subject rather than something spotted from a distance.
Yes, most Grand Cayman sites where it has been logged rate it as rare to uncommon, with only a couple of sites reporting it more consistently. Finding one usually takes a deliberate, unhurried search of coral crevices.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Freshwater Shrimp
2,168 sites
