Scientists Explain the Rare Orange Shark That Went Viral

You may have seen coverage of the viral orange shark spotted last summer off the coast of Costa Rica. A sport fisherman reeled it in and immediately knew the find was something special. It was a nurse shark (Ginglymostoma cirratum), except it was a bright shade of orange, and everyone wondered why. A new study provides an explanation for the rare, marmalade-colored animal, claiming this record of an orange shark is a first of its kind.

In the study, scientists explain that the shark is orange thanks to xanthism. Xanthism is unusually yellow pigmentation in an animal. In this case, the yellow pigment makes the shark’s skin appear orange.

[RELATED: This Rare Orange Blob Is Actually a Critically Endangered Animal]

“Xanthism, characterized by yellow pigmentation, is rare in marine species and has not been previously reported in cartilaginous fishes in the Caribbean,” the study says. Since this shark exhibited “intense yellow-orange pigmentation and white eyes,” the researchers believe the animal has a condition called albino-xanthochromism. This genetic condition has altered the levels and types of pigment present in the shark’s skin, rendering it Hi-C orange.

See photos of the rare orange shark here:

Header stock image of a nurse shark by Photographer Renzi Tommaso [email protected]/Getty Images (NOTE: The shark in this image appears orange because of the lighting.)

You may have seen coverage of the viral orange shark spotted last summer off the coast of Costa Rica. A sport fisherman reeled it in and immediately knew the find was something special. It was a nurse shark (Ginglymostoma cirratum), except it was a bright shade of orange, and everyone wondered why. A new study provides an explanation for the rare, marmalade-colored animal, claiming this record of an orange shark is a first of its kind.

In the study, scientists explain that the shark is orange thanks to xanthism. Xanthism is unusually yellow pigmentation in an animal. In this case, the yellow pigment makes the shark’s skin appear orange.

[RELATED: This Rare Orange Blob Is Actually a Critically Endangered Animal]

“Xanthism, characterized by yellow pigmentation, is rare in marine species and has not been previously reported in cartilaginous fishes in the Caribbean,” the study says. Since this shark exhibited “intense yellow-orange pigmentation and white eyes,” the researchers believe the animal has a condition called albino-xanthochromism. This genetic condition has altered the levels and types of pigment present in the shark’s skin, rendering it Hi-C orange.

See photos of the rare orange shark here:

Header stock image of a nurse shark by Photographer Renzi Tommaso [email protected]/Getty Images (NOTE: The shark in this image appears orange because of the lighting.)