Physalia daducus

All along the southern (and presumably northern) coastline of Sulepawak thrives the Bolertankulak medusa, known informally to anglophones as the “shore nettle” for its contact sting. Among coelenterates, it alone can boast a gas-filled bladder or “float” that is literally lighter than air — which largely explains its vertical form. The top three quarters of its main body extend above the bell margin and generally protrude from the water. The float crowns this mass like an onion dome, and overall it resembles a translucent chess piece when adrift.

Bolertankulak are less plentiful in the open water of the Celebes Sea than around the rocky banks of Sulepawak’s shores. Clusters are typically found lounging against tide-battered lava pillows, where their long, barely visible tentacles snare unsuspecting prey. It is usually under these circumstances that natives of the island kingdom will poison large groups of the creatures (accomplished by clouding the water with powder made from MALAYAN LAVENDER SHRIMP collected at red tide), an action that gives rise to the highlight of the annual water festivities known as the Betaralat paruvan.

For in death the Bolertankulak outdoes anything it accomplished alive, providing a spectacle unique to the greater jellyfish family: as corruption sets in, the gasses in the float ignite, and the bladder detaches from the corpse and rises into the air, incandescent. (See the Land jelly or UBURUTAN for a comparison.) It becomes no less than a sky lantern — like those made for similar events in other parts of Asia — but completely natural in origin. And while this lantern may not last as long as its paper cousins (never burning for longer than four minutes), its blaze dazzles with a rapid variety of shapes and colored flames.

From: H. Viveam Constanelle, Known Wildlife of Sulepawak: A Field Guide. Mandaroeb & Sons, 1955: p. 47.