Sepiolida

These close relatives of the cuttlefish are beyond adorable, almost caricature-like personifications of cuteness. At less than 5 cms in size they are commonly found in shallow habitats in coastal regions.  
 
Like some other marine invertebrates these animals have a close symbiotic relationship with bioluminescent bacteria, who are housed in a type of “light organ” in their skin and are provided with sugar rations for their hard work (giving the term “sugarbabies” a who new dimension). Since they are nocturnal, the light given off by the bacteria allows them to “counterilluminate” on their nightly missions as the bacteria on the underside of their body is closely adjusted to the illumination from the moon and the stars above, thus making sure their silhouette does not betray them to predators from below.