An angler at Pacific Fins Resort, a luxury resort and fishing outfitter in Guatemala, recently made quite the catch. According to a February 23 Facebook post, Paul Renfro caught and released a stunning all-white leucistic sailfish. 

“[This is a] billfish unicorn, one in a million,” wrote Pacific Fins. Renfro was aboard the outfitter’s 40-foot boat known as the Libertad when he made the catch. “Whatever you want to call it, it’s a sight you will never forget.”

The sailfish has leucism, a rare genetic disorder that results in reduced pigmentation in various species of animals. The disorder is similar to but distinct from albinism, which results from the total lack of pigmentation. 

While Renfro’s sailfish is very pale, it is leucistic and not albino because it has a normal pigmentation in its eyes; albino animals are characterized by eyes that appear pinkish when exposed to light

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Leucism is rare in fish, though scientists don’t know exactly how rare it is in wild populations. Renfro’s recent catch isn’t the first time a leucistic sailfish has been caught off the sailfish-rich waters off of Guatemala. In 2018, a German fly fisherman caught a leucistic sailfish there. That specimen had a mostly black sail, while Renfro’s fish, which wasn’t fully removed from the water, had a pale one.