BLUE-RINGED OCTOPUS. The first coin in the Luminous Marine Life series. The blue-ringed octopus is a brilliant example of how fascinating and colourful the underwater world can be. One of the most intelligent invertebrates, this amazing animal is not only smart but also highly toxic. If it feels threatened its rings illuminate several times per second. This is exactly what it does on the first coin in the Luminous Marine Life series. A colour-printed blue-ringed octopus is depicted on the coin’s reverse. When the octopus is illuminated with UV light, its blue rings begin to glow and its body changes colour from yellow-brown to green. In the background swim two peacock angelfish. A wide band, reminiscent of a an old-fashioned porthole frames the aquatic scene. As on all coins in the series, to the left and below the octopus to the right a shell and a starfish can be seen.