A few years ago, scuba divers exploring the coral reefs near Kume Island in Japan’s Ryukyu Islands made an astonishing discovery: a graveyard of small panda-like creatures. Rather than typical skeletons, these unique beings feature living panda heads still attached.

Each of these fascinating creatures measures no more than 2 cm (3 to 4 inches) long—about the length of a fingernail. One end sports a white “head” complete with a black nose spot and two panda-esque eye patches.

Their transparent bodies reveal stacks of white horizontal lines resembling bony ribs, and a distinct black dot at one end that appears to serve as a tail. It’s a truly bizarre sight.

The divers identified these peculiar creatures as a species of ascidian, commonly known as sea squirts. Shortly after the photos circulated on social media, they garnered nicknames like skeleton panda squirt—and in Japanese, they’re called “Panda Skeleton Hoya.”

The intriguing online buzz attracted the attention of sea squirt expert Dr. Naohiro Hasegawa from Hokkaido University in Japan. Upon examining the photos, Dr. Hasegawa quickly realized this sea squirt was distinct from previously known species and initiated research on this rare find.

A dedicated fan of the Panda Skeleton Squirt even contributed to a crowdfunding campaign to fund a diving trip to Kume Island.

With assistance from local fishermen, the divers successfully collected four groups of these sea squirts from depths of 10 to 20 meters (approximately 30 to 65 feet).

Back in the lab, Dr. Hasegawa confirmed that this panda skeleton squirt was unique enough to warrant its own species designation: Claverina ossipandae.

The genus Claverina was first described over 200 years ago, meaning “little bottle,” which aptly describes its transparent, bottle-shaped body, known as a zooid.

An analogous species, the bulb squirt (Claverina lepadiformis), can be found along rocky coastlines throughout Europe and bears a resemblance to a small light bulb.

The newly designated species name, ossipandae, combines “panda” with Osis, a Latin word meaning bone.

Distinguishing features of Claverina ossipandae include its unique white “ribs,” which are actually blood vessels, and intriguing black “eye” markings whose function remains unidentified.

Like other sea squirts, the panda-skeletal sea squirt is a colonial animal that feeds by filtering water through siphon tubes, extracting food particles as the water passes through their mucus-covered gills.

This process results in the expulsion of water through another siphon, hence their common name. Interestingly, some sea squirts eject jets of water when removed from their aquatic habitat.

However, sea squirts do not remain attached to rocks for their entire lives. They begin life as tadpole-like larvae, swimming freely before anchoring themselves to the ocean floor.

In their larval stage, sea squirts belong to the chordate group, which includes mammals and other vertebrates. Ascidian larvae possess a nerve cord along a rod-like structure, known as a notochord, which resembles the development in vertebrate embryos.

So, while C. ossipandae may be small and lacking fur, it bears some intriguing similarities to its namesake black-and-white pandas.

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