Marine life

Striped Pyjama Squid

Sepioloidea lineolata

A tiny, toxic, absurdly striped cuttlefish that buries itself in sand — Edithburgh's signature find.

Despite the name, the striped pyjama squid is a cuttlefish — a very small, very round one, patterned in bold brown and cream stripes that look drawn on.

It spends the day buried in sand with only the eyes exposed, emerging at night to hunt small crustaceans. That makes it a night-dive animal almost exclusively, and it is one of the finds that gives Edithburgh jetty its reputation.

It is also toxic, secreting poisonous slime, so the stripes function as a warning rather than camouflage.

A green sea turtle encounter, represented by an AI-generated editorial image.

Scientific name	Sepioloidea lineolata
Typical size	Around 5–7 cm
Peak months	June, July, August
Documented sites	3
States	South Australia

When to see them

possible good peak

Present year-round; most often found on night dives, which is when it emerges to hunt.

Where they are

Documented sites for Striped Pyjama Squid. Hover a marker for the site name.

Identification

small, rounded body with bold brown and cream stripes
no cuttlebone visible externally; the body is soft and almost spherical
often only the eyes visible above the sand during the day

Behaviour

Buries in sand by day, hunts at night.
Secretes toxic slime as a defence.
Uses the stripe pattern as aposematic warning colouration.

In-water etiquette

How divers behave around this species affects both the animal and everyone else's encounter.

Do not dig out buried animals.
Do not handle — the species is toxic.
Keep light off the animal for extended periods on night dives.

Where to see them

Sites where this species is documented as a reliable encounter.

Edithburgh JettyOne of the world's great muck dives — an unremarkable jetty hiding extraordinary small life.Rapid Bay JettySouth Australia's best-known leafy seadragon site, beneath a long jetty on the Fleurieu Peninsula.Port Noarlunga ReefA shore-accessible aquatic reserve reef reached via a jetty — South Australia's main training site.

Operators servicing those sites

Businesses documented as diving the sites above. Confirm seasonality and requirements directly.

Diving AdelaideAn Adelaide training and guided diving operation serving local sites and organised trips.

Often seen on the same dives

Giant Australian CuttlefishThe world's largest cuttlefish, gathering in tens of thousands at Whyalla each winter.Leafy SeadragonSouth Australia's emblem and the most elaborately camouflaged fish in the world.NudibranchsSea slugs of absurd colour and variety — the reason temperate Australian macro diving has a global reputation.Seahorses & PipefishCryptic, slow and protected — jetty piles and sponge gardens are where to look.Weedy SeadragonThe leafy's more widespread cousin — the signature animal of Sydney and Victorian shore diving.

Frequently asked questions

Where can I see a striped pyjama squid?

Edithburgh jetty in South Australia is the best-known site, and night dives are far more productive than daytime ones.

Last researched: September 2026. Dive businesses change frequently — confirm current services, prices and requirements directly with the operator before booking.