PORT PHILLIP BAY


Pale Octopus 

Octopus pallidus Hoyle, 1885

View scientific description and taxonomy

Scientific Details

Eight circumoral appendages; eight arms, ventrolateral tentacles absent. Mantle cavity with one opening to exterior. Arms with numerous suckers, without horny, toothed rims. Fins absent. Dorsal border of mantle fused with head. Moderate size squat and muscular species. Arms short, around 2.5 times mantle length. Ventral or lateral arms longest (typically 4>3>2>1). Webs deep, deepest around 25-40% of arm length. Web deepest on lateral arms, shallowest between dorsal arms. Web margins extending to arm tips. Suckers biserial; enlarged suckers absent. Gills with seven to nine lamellae per demibranch. Funnel organ VV-shaped, outer limbs approximately 75% length of medial limbs. Funnel locking apparatus absent. Ink sac present. Right third arm of males hectocotylized, length 80-90% of opposite arm. Ligula cylindrical and robust, 10-16% of arm length. Calamus of moderate size, 30-50% of ligula length. Hectocotylized arm with 72-86 suckers. Eggs large, around 11-13 mm. Colour typically mottled cream and orange-brown. Capable of becoming uniformly dark brown. Skin texture of close-set regular "rosette" patches forming tile-like skin sculpture. More than 20 large branched papillae can be raised on all dorsal surfaces. Several large papillae over each eye. Skin ridge around lateral margin of mantle absent.
Mantle length to 150 mm, total length to around 540 mm.

Taxonomy

Phylum:
Mollusca
Class:
Cephalopoda
Subclass:
Coleoidea
Order:
Octopoda
Suborder:
Incirrata
Family:
Octopodidae
Genus:
Octopus
Species:
pallidus

General Description

Robust, muscular octopus with short arms. Numerous regular pavement-like patches over entire body and arms. Pointed and branched fingers of skin can be raised on its body, head and above its eyes. Lacks the skin ridge (keel) of the Southern Keeled Octopus, Octopus berrima, with which it is often confused. Mantle length to 15 cm, total length to around 54 cm.

Biology

This octopus occurs on sand and mud substrates often in association with sponge gardens or beds of large solitary sea squirts. Its diet consists mainly of bivalves, which are pulled apart or drilled. It emerges at night to feed, hiding during the day in rubble or human refuse (such as bottles). This octopus lays large eggs that are attached singly to the roof of crevices or discarded bottles. The well-developed hatchlings already have good skin sculpture and camouflage. They crawl away after hatching and immediately start to forage. This octopus was previously harvested in Port Phillip Bay in baitless pot fisheries. It was sold for human consumption and used as bait.

Habitat

Sand or mud substrates, often in sponge gardens or tunicate beds, to a depth of at least 600 m.

Soft substrates

Distribution guide

South-eastern Australia.

Species Group

Octopuses and allies Octopuses

Depth

Shallow (1-30 m)
Deep ( > 30 m)

Water Column

On or near sea floor

Max Size

54 cm

Diet

Carnivore

Harmful

Potential to bite, especially if handled. Venom status unknown.

Commercial Species

No

Global Dispersal

Native to Australia

Identify

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

Author

article author Finn, J.K.

Dr. Julian Finn is a Senior Curator of marine invertebrates at Museum Victoria.

Author

article author Norman, M.

Dr. Mark Norman is Head of Sciences at Museum Victoria.

citation

Cite this page as:
Finn, J.K. & Norman, M., 2011, Pale Octopus, Octopus pallidus, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 27 Jun 2017, http://portphillipmarinelife.net.au:8098/species/4008

Text: creative commons cc by licence