Fast Facts

  • Classification
    Species
    marginatus
    Genus
    Octopus
    Family
    Octopodidae
    Order
    Octopoda
    Subclass
    Coleoidea
    Class
    Cephalopoda
    Phylum
    Mollusca
  • Size Range
    A large octopus with an armspan up to 50cm.

This octopus’s common name is derived from branching dark lines present over the body. Although having a widespread distribution throughout the Indian Ocean, little is known of the behaviour and biology of this large octopus.

Identification

Octopus marginatus can be identified by the branching dark brown veins over the mantle and down the arms. The edges of their arms are often darkened in contrast to the white-blue suckers. There is a white to cream wedge present under each eye.

Habitat

The Veined Octopus is found mainly on sandy, muddy and shelly habitats from shallow waters up to around 200m depth.

Distribution

Found throughout the tropical Indian Ocean; from Durban, South Africa across to Australia, New Guinea and southern Japan.

Feeding and diet

Octopus marginatus emerges at dusk and dawn to forage. It can feed by probing its arms down holes in the mud to catch shrimp and fish.

Other behaviours and adaptations

The Veined Octopus can bury itself in sand or mud. They also exhibit a curious behaviour adaption of using discarded clam shells and halves of coconut shells for protection. It is believed this is due to the dangerous open nature of the sandy and muddy habitats the octopus inhabits, leaving itself little protection from passing predators. Discarded halves of coconut shells are common in waters near human settlements throughout Indonesia. When two halves fitted together, the halves make a perfect refuge impossible for predators to open.

Breeding behaviours

Octopus marginatus lays up to 100 000 small eggs which hatch into tiny planktonic young. These young are carried in ocean currents, accounting for its wide distribution.

Economic impacts

The Veined Octopus is harvested in south-east Asia by trawl and traps where it is known as ‘saa liu’ (sand bird).

References

  • Norman, M., (2000) Cephalopods- A World Guide, ConchBooks, Germany (Hackenheim)
  • Norman, M & A. Reid., (2000) A Guide to Squid, Cuttlefish and Octopuses of Australasia, CSIRO Publishing, Victoria (Collingwood)