Discovery caps Horner’s MSU Texas career

Story Kathy Floyd
5 min read

Greg Broussard knew he had something different on his hands when he spent days trying to identify a spider he found on MSU Texas’ Dalquest Desert Research Station (DDRS) back in 1999.

Broussard, an MSU graduate biology student of Dr. Norman Horner’s, found the unknown specimen in a trap while conducting a spider survey at the DDRS in West Texas’ Chihuahuan Desert. Using the taxonomic ranking system, he worked from the bottom, trying to find a species, then a genus, then family. “Dr. Horner told me I had it in the wrong family, but after four days, he couldn’t fit it in either,” Broussard said. “At the time, he already had 30 years of studying spiders and he couldn’t place it. It’s neat to think that I stumped Dr. Horner.”

Horner, Professor Emeritus of Biology and former Director of Natural Laboratories at MSU Texas, already had a highlight-filled career of nearly 40 years at MSU, including being named Hardin Professor in 1976, receiving the Faculty Award in 1983, and serving as Dean of the College of Science & Mathematics from 1999 until his retirement in 2006.

Because of his special interest in spiders, he was part of a worldwide group of scientists. “Studying spiders allowed me to meet and become friends with fellow araneologists across the U.S. and other parts of the world,” Horner said. He would need to call on that network of spider specialists to help with Broussard’s discovery, and what he considers the high point of his career.

In a location as remote as the DDRS, finding a new species would not have been surprising, but to find a new family was unexpected. “The bottom line is this is a big deal in the world of spiders. Finding a spider that can’t be identified is rare,” said Horner. The “Texas Mystery Spider,” as it was called for 15 years, puzzled nine world-renowned spider taxonomists.

From Horner, the mystery spider went up a chain of hierarchy in the zoology world. Horner sent the spider to James Cokendolpher, former assistant curator and research scientist at Texas Tech University (an MSU alumnus and former student of Horner’s), who sent the spider to Darrell Ubick, spider taxonomist at the California Academy of Science, who sent the mystery spider to the world’s leading spider taxonomist, Dr. Norman Platnick at the American Museum of Natural History in New York.

In 2008, while the spider was making the rounds in search of an identity, Dr. David Lightfoot from the Museum of Southwestern Biology at the University of New Mexico found a specimen on top of harvester ant beds approximately 208 miles south of the DDRS in Cuatro Ciénegas, Mexico.

He carried specimens back to UNM, where he gave them to his museum’s former senior collection manager, Dr. Sandra Brantley, for identification. “She had no idea what they were and sent them to Platnick,” Horner said. Platnick told Brantley that this was the same spider Horner had been working on. Horner and Lightfoot exchanged information, with Lightfoot making the association with the harvester ants.

Platnick retired in 2014 and turned the project over to Dr. Martin Ramírez of the Museo Argentino de Ciencias Naturales in Buenos Aires, Argentina, and one of the world’s leading authorities on spider DNA analysis.

Ramírez led an international team of 10 scientists as they analyzed the mystery spider’s morphology and six mitochondrial and nuclear DNA markers to unravel the evolutionary affinities of the species, which turned out to be the sole representative of an entirely new lineage. The spider is not closely related to any other known family. They described the species in detail and named it Myrmecicultor chihuahuensis.

The spider is associated with at least three species of harvester ants, which is the reason for its name: “myrmex” is the ancient Greek word for ant, and “cultor” is Latin for worshiper, follower.

In 2015, Horner contacted Dr. Paula Cushing from the Denver Museum of Nature and Science. She has spent much of her career working with spider and ant relationships. Cushing excavated entire nests of N. albisetosis ants on the DDRS, and found the spiders living in ant chambers. What they eat in there is a mystery, but because of their small size they likely prey on other insects living with the ants.

Twenty years after its discovery, the new family of spiders was officially recognized by the world’s taxonomists last summer, increasing the number of spider families to 120. According to Platnick, new families have been recognized based on previously unknown species only seven times in the last 88 years – in 2012, 1980, two families in 1955, 1947, 1940, and 1931.

“There are many more things we need to find out, such as what they’re really eating and why they’re living with three different kinds of ants,” Horner said.

Of 71 new animal and plant species discovered in 2019, the California Academy of Sciences listed the spider among its top new discoveries of the year, news of which was picked up by CNN.

Broussard earned his bachelor’s degree in biology in 1998 and his master’s in 2002. He now teaches biology at Central New Mexico Community College in Albuquerque. He is a Holliday High School graduate with family still in the area. His brother Scott teaches in Henrietta and his nephew Braden is a 2019 graduate of MSU Texas.

Horner says that watching students start as freshman and obtain their bachelor’s and master’s degrees, with some going on for their Ph.D., then having productive careers of their own, has been as rewarding as the honors he has earned. And Broussard is one of those students.

Broussard says that Horner had the biggest influence on what he does as a teacher. “I couldn’t have had a better mentor,” Broussard said. “He shaped my career.”