This is a picture of the Sparkling Enope squid - also known as the flirefly squid - washed up on the beach at Toyama Bay in Japan.
The squid are are roughly 15cm in length and die after only a year of life. Found in the Western Pacific ocean, they live at depths of 183-366m and only come to the surface at night to show off their brilliant bioluminescence. The squid's photophores* are located at the end of each tentacle.
The Sparkling Enope squid is the only species of cephalopod that has evolved to be able to see colour in three visual pigments. Scientists think that this is to help them distinguish between ambient light and their own bioluminescence.
The firefly squid lights up for two reasons: the lights on the tentacle can flash to attract fish that the squid feed on, and lighting up their entire bodies help to attract a mate during the months of March to June.
* The organs that produce the light.