Red and white bands and a pair of antennae twice the length of the animal, waving from under a ledge. Six centimeters (2.4 in), and it runs a business.
The antennae are the sign over the door. A cleaner shrimp advertises from a fixed address, fish come to it, and the shrimp works over their skin, gills and mouth for parasites, dead tissue and food scraps. Big predators queue and hold still with their mouths open; the shrimp walks inside and comes out again. The arrangement holds because a cleaner is worth more alive than eaten, and it is one of the clearest cases of an animal trading a service for safety.
They pair for life. A male and a female hold one station together, and pairs are territorial about it - two pairs in one cave will fight until one leaves.
Because it is nocturnal as well, the same ledge that looks empty by day has the pair out in the open at night. Recorded down to 210 m, which for an animal this conspicuous is unexpected.
- red and white banded body and legs, three white bands across the tail
- very long white antennae, waved constantly from the entrance of a hole
- almost always in a pair, hanging upside down under a ledge
- length up to 6 cm
