Utah’s Great Salt Lake is roughly eight times saltier than the ocean in some stretches, a chemical environment so punishing that only two animals were previously known to survive in it: brine shrimp and brine flies. Now a third has joined the list. Scientists have formally described a never-before-recorded species of roundworm living among mineral formations on the lakebed, making it the third multicellular animal documented in one of the harshest aquatic habitats on Earth.
The nematode, named Diplolaimelloides woaabi, measures less than a millimeter long. Its formal description, published in the Journal of Nematology, is based on both physical examination under high-powered microscopy and genetic sequencing of its 18S rRNA gene. Those two independent lines of evidence confirmed the worm is distinct from every known relative in its family, Monhysteridae, a group of free-living nematodes found in aquatic environments worldwide.
“This is the first new metazoan species described from Great Salt Lake in more than a century,” said Michael Werner, a biologist at the University of Utah who co-led the research, in a university statement distributed through EurekAlert.
Where the worm lives, and what sustains it
The discovery traces back to field expeditions in 2021 and 2022, detailed in an earlier peer-reviewed study in Proceedings of the Royal Society B. That research established that nematodes in the Great Salt Lake are strongly associated with microbialites: layered structures built from minerals and microorganisms that line portions of the lakebed like a living reef.
Microbialites turn out to be biologically richer than the barren-looking lake might suggest. Separate research published in Applied and Environmental Microbiology documented an unexpected abundance of phototrophs, light-harvesting microorganisms, inside the mats coating these formations. Those microbial communities, along with dense bacterial populations, likely provide a food source for the worms. The result is a self-contained ecosystem tucked inside the mineral structures: bacteria and algae feed the nematode, and the microbialite itself offers a buffer against the open water’s extreme chemistry.
That chemistry varies across the lake. A railroad causeway built in the 1950s divides the Great Salt Lake into a north arm and a south arm with markedly different salt concentrations. Research on microbialite responses to this human-made gradient shows that both the mineral frameworks and their resident microbes differ substantially between the two sides. Whether D. woaabi inhabits microbialites across the full salinity spectrum or is confined to certain zones has not yet been determined. Existing records are tied to specific sampling sites, so the worm could be more widespread, or more restricted, than current data show.
A name chosen with the Shoshone Nation
The species name carries cultural significance. Before finalizing it, the research team consulted with the Northwestern Band of the Shoshone Nation, whose ancestral ties to the Great Salt Lake region predate European contact by thousands of years. The word “woaabi” was approved through that consultation, according to the University of Utah statement. The deeper meaning of the term in the Shoshone language has not been elaborated in the published scientific papers or supplementary materials, leaving an important dimension of the story still to be told from the perspective of Indigenous knowledge and naming traditions.
What scientists still don’t know
Key questions remain open. No published data yet describe the worm’s full reproductive cycle or how its population fluctuates with seasonal salinity swings. Researchers have not determined whether the species produces desiccation-tolerant eggs or other resistant life stages that could help it ride out rapid environmental shifts. And while the available studies show a strong association between nematodes and microbialites, they have not ruled out the presence of worms in nearby sediments or other microhabitats. Without targeted surveys comparing microbialites to surrounding substrates, it is unclear whether D. woaabi is an obligate specialist or a more flexible inhabitant of hypersaline lake bottoms.
No follow-up sampling from 2023 onward has appeared in the peer-reviewed record as of June 2026. The formal species description draws on specimens collected during the original 2021 to 2022 expeditions, so there is no verified information yet on whether the worm’s abundance or distribution has shifted as the lake’s conditions continue to change.
Why a tiny worm matters for a shrinking lake
The Great Salt Lake has been losing water for decades, driven largely by upstream diversions for agriculture and municipal use. As the lake shrinks, salinity climbs, and the microbialite habitats that support D. woaabi, along with the brine shrimp and brine flies that feed millions of migratory birds, come under increasing stress. The lake’s brine shrimp harvest also supports a commercial industry worth hundreds of millions of dollars annually, giving the ecosystem economic stakes that extend well beyond its shoreline.
In that context, the new nematode is more than a line on a species list. It is evidence that even in a place that looks nearly lifeless, intricate biological networks persist, quietly built around structures most visitors would never notice. If microbialites degrade or disappear, the tightly coupled community of microbes and animals they host could unravel. D. woaabi is a small organism carrying a large message: the Great Salt Lake’s ecosystem is more complex, and more fragile, than it appears.
More from Morning Overview
*This article was researched with the help of AI, with human editors creating the final content.
