A rare white namako (sea cucumber) has wowed visitors to an aquarium in the city of Fukuoka recently, prompting many to make their wish for good luck on the marine creature.

The white sea cucumber is thought to be an albino, with its pigments mutated for unexpected reasons. The rare marine life recently debuted at the Marine World Uminonakamichi aquarium in Fukuoka.

Aquarium official Takumi Orii pitched the new exhibit, saying: "It may bring good luck. We'd like people to come and see it."

The namako is about 15 cm long and weighs 75 grams. A local fisherman found it in January and offered it to the aquarium.

With the assistance of aquarium staff, visitors can even "feel" the namako by touching it, the aquarium said.