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Parasite Naming

United States Fish and Wildlife Service fish biologist Eric Leis recently named an aquatic parasite he discovered, drawing below, after his parents. The gesture was a way of thanking them for supporting his interest in science when he was a kid.

After graduating from college, Eric Leis meant to thank his parents for their support. He never got around to sending a card, but 10 years later he showed his gratitude — by naming a parasite after them.

Leis, a biologist with the U.S. Fish and Wildlife Service, published an article last month in the journal Parasitology Research on one of two new species he discovered in the gills of a Mississippi River catfish.

Ligictaluridus michaelalicea

Ligictaluridus michaelalicea, a parasite that lives in catfish gills, was discovered by U.S. Fish and Wildlife Service biologist Eric Leis, who named it for his parents. 

Measuring a little over a millimeter in length, Ligictaluridus michaelalicea is a flatworm named for Michael and Alice Leis.

“I just always wanted to give them a card and say thanks,” Leis said. “But time slips by.”

Growing up on the family farm near Cashton, Leis, 36, was fascinated by the outdoors. Between chores he would examine the parasites that burrowed in the backs of the cows, though it wasn’t until he was in college that he learned what they were called.

“If he wasn’t fishing with his grandpas, he was out collecting bugs, anything that crawled,” Michael Leis said of his son.

His mother helped with science fair projects and taped “Nature” and other science shows on the VCR. His father taught him how to observe the environment, where to sit when hunting deer.

“They were always just right there,” Leis said.

Michael Leis

Michael Leis

Alice Leis said her son was always checking things out, even when the rest of the family didn’t share his curiosity.

“We were a busy family. We’re thinking, ‘Come on, we’ve got to go,’” she said. “Things you don’t think are significant turn out to be major factors in their life.”

Alice Leis

Alice Leis

When he was in middle school, his parents gave him a microscope. He still remembers looking at snowflakes under the lens as he sat outside with his parents on a bitterly cold night.

“It changed my view of the world,” he said.

Leis went on to study biology at the University of Wisconsin-La Crosse and earned a master’s degree in 2007 before going to work for the Fish and Wildlife Service.

In 2015, he was examining cysts on the gills of a flathead catfish — under a much more powerful microscope in his Onalaska lab — when he noticed two worms that didn’t match any of the known catfish parasites. It turned out both were undiscovered species.

One, which was formally identified in a paper published last year, he named for his mentor, former Fish and Wildlife Service biologist Becky Lasee. The other, which took a little longer to go through the peer review process, he named for his parents.

Leis, who’s working on identifying what could be two additional parasites, notes there are more than 15,000 new species discovered every year.

Eric Leis microscope

Eric Leis with the microscope his parents gave him for Christmas when he was in middle school.

Despite the uncharitable portrayal of parasites in popular culture, Leis said the Ligictaluridus michaelalicea doesn’t seem to have any negative effects on catfish.

“There’s always a balance between the parasite and the host,” he said. “It’s unsightly and disgusting, but they’re just part of life.”

Leis’s parents got to look at their namesake through the microscope before the slide was sent to the Smithsonian Institution for preservation.

“It’s quite an honor,” Michael said. “Not many people can say that, I guess.”

Parasite Naming

Eric Leis, a fish biologist with the U.S. Fish and Wildlife Service peers into a microscope Tuesday at his lab in Onalaska. Leis recently named a parasite he discovered, Ligictaluridus michaelalicea, after his parents, Michael and Alice Leis of Cashton.

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Rhymes with Lubbock. La Crosse Tribune reporter and data geek. Covers energy, transportation and the environment, among other things.

(1) comment

Mo' Money Scott Walker

Way to give back Eric!

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