Meet the “Underwater Panda”: This sea creature found 20 metres below Japan’s Coast, is barely an inch long

Japan’s coast discovered a panda-like marine creature at 10–20 metres deep. (Image: Naohiro Hasegawa/Hiroshi Kajihara)

• A new sea squirt species, Clavelina ossipandae, found near Japan.
• Nicknamed "skeleton panda sea squirt" for its panda-like markings.
• Formally described in 2024, its abundance in the wild is unknown.

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Scuba divers exploring the waters off Kumejima, Japan, shared images of a tiny marine creature resting on coral. It appeared to have a white body with black patches arranged like a panda’s eyes and nose.

Social media quickly embraced it as a “cute underwater panda.” But this was not a baby mammal lost at sea. It was something far stranger and far more scientifically exciting.

Not a Panda, But a Sea Squirt

Researchers later confirmed that the animal is a newly described species of sea squirt named Clavelina ossipandae. Sea squirts belong to a group of marine invertebrates known as tunicates. They may look simple and gelatinous, but they are biologically fascinating.

In fact, tunicates are considered distant relatives of vertebrates, meaning they share evolutionary roots with animals that have backbones. The species was formally described in 2024, though divers had been photographing it for years before scientists took a closer look.

The Skeleton Panda Sea Squirt (Clavelina Ossipandae) is a translucent reef-dwelling creature whose rib-like structures and panda-like markings give it a spooky, animated look. Found in Southeast Asia, it harmlessly filters seawater and helps keep coral ecosystems healthy. pic.twitter.com/ktTZyjjhwP

— Massimo (@Rainmaker1973) February 19, 2026

Why Does It Look Like a Panda?

The resemblance is purely coincidental. The white “bone-like” markings inside its translucent body are actually visible blood vessels running through its gill structures. The black patches, which resemble panda eyes, are pigmentation patterns whose exact function remains unclear.

The nickname “skeleton panda sea squirt” stuck because of this unusual contrast of pale internal structures framed by bold dark spots.

Tiny, Transparent and Living in Shallow Waters

This small marine organism grows to less than an inch long. It attaches itself to hard surfaces such as coral reefs or rocky substrates and feeds by filtering plankton from seawater.

Like other members of the genus Clavelina, it lives in relatively shallow waters, typically within diving depth ranges. Its habitat near Japan’s reef ecosystems suggests that there may be more undiscovered micro-species hiding in plain sight beneath popular diving spots.

Is It Rare or Just Rarely Documented?

There is currently no clear data on how abundant Clavelina ossipandae is in the wild. It may be genuinely rare, restricted to specific reef systems near Japan. It is possible that the species has simply gone unnoticed for years. Scientists are trying to know about this unique species.