In this 2011 file photo Leonard Krishtalka, Kansas University professor of ecology and evolutionary biology and director of KU's Natural History Museum, stands next to a triceratops fossil.

The jaw of a Nyctitherium krishtalkai, a prehistoric shrew-like mammal named after Leonard Krishtalka, director of the KU Museum of Natural History and Biodiversity Institute. Photo courtesy of Denver Museum of Nature and Science.

Fifty million years ago central Wyoming was dense rainforest. In the lush undergrowth of the forest floor, one of the world’s early mammals, Nyctitherium krishtalkai, scampered around looking for bugs. It was a diminutive critter, resembling a modern shrew. “You would have barely noticed it,” said one of the animal’s discoverers, Richard Stucky, a curator at the Denver Museum of Nature and Science.

If the name “krishtalkai” sounds familiar, you’re not going crazy, nor did you spontaneously acquire knowledge of taxonomy or Latin. The recently discovered animal was named after a well-known figure at Kansas University for almost 20 years.

A few geological epochs after Nyctitherium krishtalkai went extinct, Leonard Krishtalka, director of KU’s Natural History Museum and Biodiversity Institute since 1995 and the man who put the “Krishtalka” in krishtalkai, labored around the same patch of ground.

But by then central Wyoming was semi-arid scrubland, and instead of scrounging for bugs, Krishtalka was looking for remains of the family of mammals that the Nyctitherium krishtalkai belonged to, and which gave rise to modern shrews, hedgehogs and moles.

Krishtalka played a major role in defining the taxonomy of the nyctitheres, which includes Nyctitherium krishtalkai. That is one reason Stucky named the animal after him, though he has personal reasons as well.

Decades ago Krishtalka worked with Stucky as a mentor and then a colleague, the two of them outlining the evolutionary history of mammals found in the sediment at Buck Spring Quarries in Wyoming. Often during their work together they would “discuss vociferously” matters of evolution, taxonomy and paleontology before getting a beer together at the end of the day.

“We worked side by side together,” Stucky said. “It was one of the best collaborative relationships that I can imagine you can have.”

Nyctitherium krishtalkai, which Stucky discovered with Michael Christiansen of the Massachusetts Institute of Technology, is the most primitive species in its genus discovered so far, Stucky said. It went extinct about 44 million years ago, likely because of habitat changes that made the rainforest more like savannah. Those changes, in turn, were likely related to a changing climate that became cooler and fluctuated more with the seasons.

Krishtalka, who is currently in Italy and could not be reached for comment, said in a KU press statement: “I spent many years uncovering and studying these and other extinct mammals with Dr. Stucky, and I am humbled by his recognition of our wonderful collegiality and accomplishments in bringing to light the ancient world of mammals in North America.”