ASC Contributes to Discovery of New Diatom Genus

By Emily Stifler Wolfe 

Forming the base of nearly all aquatic food chains, diatoms are essential to the health of the planet. These single-celled photosynthetic plants account for around 40% of carbon fixation and oxygen production worldwide, according Dr. Loren Bahls, curator of the Montana Diatom Collection.

“Diatoms appeared sometime during the Cretaceous, about the same time as flowering plants and when dinosaurs ruled the land,” explains Dr. Bahls, who has been an ASC partner since 2012. “When you slip on the rocks in a mountain stream, you are slipping on a thin layer of diatoms and the mucilage they produce.”

With help from ASC hikers, climbers and backpackers, Dr. Bahls recently discovered a new genus of diatom, Kurtkrammeria, named after the German diatom researcher Kurt Krammer. Craig Weiland has been one of the most active and productive of the ASC volunteers on this project, and Dr. Bahls chose Kurtkrammeria weilandii (pictured at left) as the type species for the new genus Kurtkrammeria. K. weilandii, named for Weiland, exhibits all of the physical features that distinguish the new genus from other genera, and is endemic to the Pacific Northwest.

“Most of the samples that I used to describe the new genus were collected by ASC volunteers from small lakes and ponds in the mountains of the Pacific Northwest,” Dr. Bahls said. “The new genus is found only in remote bodies of water with difficult access. I couldn’t have done it without their help.”

In biological classification, a species is the smallest unit; next comes genus, family, order, class and phylum. While several thousand species of freshwater diatoms exist in the United States, there are only about 180 genera. This new genus will help taxonomists better classify diatoms and recognize relationships among and differences between similar taxa. ASC volunteers contributed samples for the study from Washington, Oregon, Idaho, Montana, Wyoming, California, Alberta and British Columbia. 

In the big picture, studying diatoms can teach us more water quality, ecology and climate. 

Different diatom species have distinct tolerances and ranges for environmental variables including pH, salinity, nutrient concentration, suspended sediment, elevation and human disturbance, so scientists use them extensively in environmental assessment and monitoring, according to Diatoms of the United States. In addition, because diatom cell walls are made of either silicon dioxide—essentially glass—or opal, they don’t decompose, they can be used to study historic climates. 

The discovery is a first for Dr. Bahls, who has been studying diatoms for 49 years.

“Diatoms are the charismatic microflora,” he says. “They are to microscopic organisms as grizzly bears are to mammals. They are beautiful for their intricate designs and symmetry and amazing for their incredible variety. Once you’ve seen a diatom, any diatom, under a quality microscope, you’re hooked!”