A shrimp the size of a grain of rice, olive-brown with white saddles edged in electric blue, sitting on an anemone with its abdomen curled up over its back and waving. The waving never stops, and it is what named the animal.
What the display is for is not settled: it may advertise the shrimp to its own kind, or signal to the anemone, or make a very small animal look like something moving in the current rather than food. They live in groups of a few on one host, and the whole group waves.
Living on an anemone requires not being stung, and this shrimp acclimates the same way clownfish do - by touching the tentacles repeatedly until the anemone stops treating it as prey. It then feeds on mucus, scraps from the host's meals and detritus, and shelters among the tentacles whenever anything approaches.
It is one of the standard subjects of macro photography here for good reason: it is common, it stays put, and it is small enough that most divers swim past a hundred without seeing one.
- tiny olive-brown shrimp with white saddles edged in blue
- abdomen held curled up over the back, waving constantly
- in small groups on a single anemone
- length up to 1.6 cm
