Violet blanket octopus (Tremoctopus violaceus) is an example of extreme sexual dimorphism in a species: females can be up to 2m in length whereas males are a tiny 1-2cm creatures. Jewelled Umbrella squid (Histioteuthis bonnellii).The jewels of this squid are bioluminescent photophores that cover its body and provide the most beautiful play of colours in deep see.
From: Mollusques méditeranéens by Jean Baptiste Vérany (1851)
A rather large species for its genus, this cockeyed squid lives throughout the Atlantic Ocean with a mantle length up to 13 in. There may be several separate populations of this squid throughout its region.
The small “jewels” along its body are photophores. All species have the same number of photophores with the same pattern of distribution.
Their population is somewhat unknown, as their habitat is so wide, and their numbers so unevenly distributed. They are known to be vulnerable to over fishing and pollution.