''Sepiadarium austrinum'', the southern bottletail squid,
is a species of
cuttlefish
Cuttlefish, or cuttles, are Marine (ocean), marine Mollusca, molluscs of the order (biology), suborder Sepiina. They belong to the class (biology), class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique ...
in the genus
Sepiadarium. It was first described by
S. Stillman Berry
Samuel Stillman Berry (March 16, 1887 – April 9, 1984) was an American marine zoologist who specialized in cephalopods.
Early life
Berry was born in Unity, Maine, but the family home was the Winnecook Ranch in Montana, which had been found ...
in 1921
based on a specimen found in St. Vincent Bay in South Australia.
Description
''S. austrinum'' is very small and round, with kidney-shaped fins on the back third of its body.
It has a mantle length of up to three centimeters
and a total length of up to four centimeters.
It can be transparent, yellow, or orange, with egg-shaped white
leucophore
Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast ...
s.
''S. austrinum'' has ten arms and tentacles
with nine or ten rows of suckers on each arm.
Distribution
''S. austrinum'' is found in the southern
Indo-Pacific
The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...
in southern Australia,
with a small population in the
Spencer Gulf
The Spencer Gulf is the westernmost and larger of two large inlets (the other being Gulf St Vincent) on the southern coast of Australia, in the state of South Australia, facing the Great Australian Bight. It spans from the Cape Catastrophe an ...
.
They are mostly found in sandy habitats in shallow,
sheltered waters
at depths up to 65 meters.
Behavior
''S. austrinum'' buries itself in the sand during the day and feeds at night.
It is able to produce slime
when threatened.
Diet
''S. austrinum'' is carnivorous.
It feeds in the sand and near seagrass beds.
Its diet is mostly composed of small fish and crustaceans, including amphipods
and especially benthic isopods.
Reproduction
''S. austrinum'' reproduce from a young age;
immature females can also store sperm.
Individuals mate with multiple partners. Mating is initiated by males and there is no observed courtship behavior.
Males pass sperm packages to the female, who stores them in a pouch below her mouth. Males can also use a special arm to remove the sperm of other males from the pouch.
Females can also remove sperm from the pouch,
and regularly consume spermatophores.
They fertilize eggs by passing them over the pouch.
Clumps of eggs
are covered in sand and attached to seaweed or seagrass.
Life cycle
''S. austrinum'' is an annual species.
Juveniles settle quickly after hatching.
Relationship to humans
''S. austrinum'' survives well in aquariums, which may make them of commercial interest.
They may bite when handled.
References
{{Taxonbar, from=Q2691649
Cephalopods described in 1921
Sepiadarium