The beach at Tannan Bay in Pingtan county, east China's Fujian province, has recently been dotted with blue luminous spots at night.

One woman who seemed amazed by the flickering sand beneath her feet compared the scene to the movie Avatar.

And a man who had just proposed to his girlfriend wondered if the phenomenon was due to some kind of firefly.

Wang Yun, director of the local station promoting aquaculture methods, said that the little blue creatures are ostracods, which are small crustaceans and are sometimes called seed shrimp.

Wang also said that the ostracods which have a blue glow in the dark are sometimes referred to as "blue sand" or "blue tears," and the effect is due to a light organ that some ostracods possess, which produces luminescent chemicals. Most of the ostracods use the light as a defense mechanism, while some use it for mating.

Edited by Chen Zhilin and Niva Whyman