PORT PHILLIP BAY


Southern Bottletail Squid 

Sepiadarium austrinum Berry, 1921

View scientific description and taxonomy

Scientific Details

Ten circumoral appendages, eight arms and two ventrolateral tentacles. Mantle cavity with three openings to exterior. Arms and clubs at the tips of the tentacles with numerous suckers, each armed with a horny, toothed rim. Tentacles contractile and retractile into pockets between arms III and IV. Mantle edge near mantle cartilages straight. Fin not joined posteriorly. Dorsal border of mantle fused with head. Non-hectocotylised arm sucker arrangement biserial, sometimes tetraserial at middle and distal tips of arms. Left ventral arm of males hectocotylised. Base of hectocotylus with nine to 10 pairs of normal suckers replaced by single series of conical lamellae on distal end of hectocotylised arm. Tentacle club with six suckers in transverse rows. Internal shell absent.
Body colour transparent, yellow or orange, with large ovoid leucophores.
Mantle length to 30 mm

Taxonomy

Phylum:
Mollusca
Class:
Cephalopoda
Subclass:
Coleoidea
Order:
Sepiida
Family:
Sepiadariidae
Genus:
Sepiadarium
Species:
austrinum

General Description

Tiny round, bottom living squid. Small pair of kidney-shaped fins on sides of body encompassing the rear third of the body. Orange or yellow in colour, comprised of large pale spots (leucophores) scattered over the body, head and arms. Underside of the head and body covered in regular small rounded glands that produce slime (mucous). Mantle length to 3 cm.

Biology

These small squids hide during the day by wriggling into the sand and using two arms to rake sand grains over their heads and bodies. At night, they emerge to hunt for small crustaceans, particularly isopods. If attacked they squirt a large amount of slime from glands under their body. The slime appears to contain chemicals that deter or scare off predators. Its chemical composition is still unknown. Females lay eggs in clumps, glued together and covered in sand grains, usually at the bases of seaweeds or seagrasses.

Habitat

Sand and mud habitats in coastal waters, often near seagrass beds to a depth of at least 65 m.

Seagrass meadows

Soft substrates

Distribution guide

Southern Australia.

Species Group

Octopuses and allies Squid

Depth

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

Water Column

On or near sea floor

Max Size

3 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, Southern Bottletail Squid, Sepiadarium austrinum, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 16 Dec 2017, http://portphillipmarinelife.net.au:8098/species/4076

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