The University of Florida’s Forest Entomology Lab hosts the world’s largest cryo-collection of bark and ambrosia beetles. In April 2019, it surpassed 20,000 vials, which contain more than 115,000 individual beetle specimens. (Photo credit: Jackson Landers, University of Florida)

By Jackson Landers

In early April, the University of Florida’s Forest Entomology Lab filled its 20,000th vial of bark- and ambrosia-beetle samples.

Vial No. 20,000 contains specimens of Gnathotrichus denticulatus, a pine-dwelling ambrosia beetle, collected in Arizona by Andrew Johnson, Ph.D., a UF faculty member who specializes in bark and ambrosia beetle identification and phylogeny in the lab.

The beetles in the collection “are a variety of species from all over the world, trapped by all kinds of different methods,” says Johnson. “Some of them represent vouchers for studies. … Some of them are large numbers [per vial] used for training purposes. Some of them are the data for ecological studies.”

The collection was started by the lab’s principal investigator, Jiri Hulcr, Ph.D., during his work as a research station manager in Papua New Guinea in the year 2000, in a collaboration of PIs from the South Bohemia University, the Smithsonian Institution, and the University of Minnesota.

“One of the perks of the job was being able to start a research project on my own,” says Hulcr, “so I started collecting bark beetles. It turned out that even the first few were incredibly interesting and also very poorly known, so I started a large experiment where I reared thousands of them, and that is what started our collection.”

The University of Florida’s Forest Entomology Lab hosts the world’s largest cryo-collection of bark and ambrosia beetles. In April 2019, it recorded its 20,000th vial, containing specimens of Gnathotrichus denticulatus, a pine-dwelling ambrosia beetle, collected in Arizona. (Photo credit: Jackson Landers, University of Florida)

Specimens in the University of Florida Forest Entomology Lab’s cryo-collection of bark and ambrosia beetles are held continuously at –80 degrees Celsius, which preserves them for study of the beetles’ DNA and fungal symbionts. (Photo credit: Jackson Landers, University of Florida)

During the ensuing 19 years, it has grown to become the largest cryo-collection of bark and ambrosia beetles in the world. Some other institutions, including the Smithsonian National Museum of Natural History, have greater species diversity, but their collections are largely pinned at room temperature rather than frozen, limiting their utility for the study of DNA and the beetle’s fungal symbionts. All of the beetles (which number somewhere over 115,000 among the 20,000 vials) in the UF collection are held continuously at –80 degrees Celsius.

However, the collection frequently loses specimens, as well—deliberately.

“We send reference collections out all around the world,” Johnson says.

One of the strategic goals of the UF collection is to provide extra specimens that are regularly grouped together and shipped out as reference collections that are kept on hand for other scientists and foresters who need to rapidly identify bark and ambrosia beetles in the event of a suspected outbreak that threatens forests. Funding for the reference collections has been provided by organizations including the United Nations and U.S. Department of Agriculture.

A digitized database of the collection is being constructed and is expected to be available online by the end of 2019. It will include photos, taxonomy and information about interactions between the insects, plants and fungi. Stay tuned!

Jackson Landers is strategic science communicator at the UF/IFAS Emerging Threats to Forests Research Group. Email: jack.landers@gmail.com.