Common Names: Blanket Octopus
Blanket Octopus are 4 species of the genus Tremoctopus. These pelagic octopuses are found throughout the world's tropical and sub-tropical oceans from the surface to moderate depths.
Blanket Octopus Video
There are four different Tremoctopus species:
- Tremoctopus gelatus, commonly known as Gelatinous Blanket Octopus
- Tremoctopus robsoni
- Tremoctopus gracilis, commonly known as Palmate Octopus
- Tremoctopus violaceus, commonly known as Common Blanket Octopus or Violet Blanket Octopus
Blanket Octopus Description
These octopuses exhibit an extreme degree of sexual dimorphism. Females are large and muscular and may grow to over 2 metres in total length. On the other hand males are very small, reaching a length of only 1-2 cm not even an inch!
They are best known for their long transparent webs that connect the dorsal and dorsolateral arms of the adult females whereas the other arms are much shorter and lack webbing.
Males develop a specially modified third right arm used for storing the sperm. This structure is known as the hectocotylus.
Contrary to most octopuses the blanket octopus does not use ink to avoid potential predators. When females are threatened, they unfurl their large net-like membranes that spread out and billow in the water, greatly increasing their apparent size.
Blanket Octopus Predators
The Mediterranean spearfish (Tetrapturus belone) and the swordfish (Xiphias gladius) are known to feed on the various tremoctopus species.
Blanket Octopus Reproduction
During mating, the hectocotylus is detached and crawls into the mantle of the female to fertilise her eggs. It is hypothesised that the male dies after a while. Females usually carry well over 100,000 and up to 150,000 tiny eggs which are attached to a sausage-like calcareous secretion that is held at the base of the dorsal arms. They are carried by the female until hatching.
Other Interesting Facts
Blanket octopuses are immune to the poisonous Portuguese man o' war. Males and immature females rip off their tentacles and use for defensive and possibly offensive purposes.,