Julie Jung
Scientists have identified roundworms in the USA that belong to at least one species never described before.
Scientists at the University of Utah identified Great Salt Lakeus United States, small nematodes (round worms) that belong to at least one never before described species — and there is evidence that there may be two new species.
The discovery is described in a and includes the assignment of a name that recognizes the indigenous people whose ancestral lands encompass the lake.
The species now described is called Diplolaimelloides woab and, according to researchers, appears to exist only in this Great Salt Lake.
The team, led by Michael Werner, assistant professor of Biology, worked with the Northwestern Band of the Shoshone Nation on the nomination process. It was the community elders who suggested “Save”, an indigenous word meaning “worm”.
Nematodes are among the most widespread animals on the planet, capable of survive in extreme environments — from polar ice to deep-sea hydrothermal vents — and also in common places, like the soil in a backyard. Most measure less than 1 millimeter, which helps explain why they go unnoticed.
Despite being considered the most abundant animal phylum, with hundreds of thousands of identified species, there has been no confirmed record of nematodes in the Great Salt Lake until 2022.
This first sign appeared in expeditions carried out by kayak and bicycle, led by Julie Jung, then a postdoctoral researcher in Werner’s lab.
The team collected nematodes in “microbialites”, hardened mound-like structures that cover parts of the lake bottom, describes the .
The presence of these organisms was reported in an article the following year, but it was only now possible to taxonomically confirm that it was, in fact, a new species — a work that, according to Jung (now a professor at Weber State University), required three additional years.
With this discovery, nematodes become part of a very restricted group of multicellular animals known to live in the highly saline waters of the Great Salt Lake.
Until now, only two other groups were recognized as residents: brine shrimp (brine shrimp) e brine flies (brine flies), essential for sustaining large populations of migratory birds during seasonal stops.
Ongoing research also suggests the existence of a second population genetically distinct among the specimens collected, which may point to another undescribed species. However, scientists emphasize that more work will be needed to confirm this hypothesis.
How did it get there?
In addition to adding known biodiversity to the lake, the discovery opens new questions about the origin and ecological paper of these worms. Researchers suspected from the beginning that the nematodes belonged to a group known to adapt to extreme environments, including high salinity. Genetic and taxonomic analyzes indicate that the new species belongs to the genus Diplolaimelloides, whose members are normally found in coastal areas and brackish waters.
This makes presence in the Great Salt Lake particularly intriguing: the lake is approximately 1,280 meters above sea level and approximately 1,300 kilometers from the nearest sea.
One hypothesis, proposed by Byron Adams, nematologist at Brigham Young University, suggests a remote connection to the geological past: Millions of years ago, during the Cretaceous, the region was part of the western margin of a vast inland seaway.
Another hypothesis, even more unlikely according to the team itself, is that the nematodes arrived transported by migratory birds, trapped in the feathers, coming from other saline lakes.
In the laboratory, scientists also observed a disconcerting pattern: in the lake, as females represent more than 99% of the individuals collected, but in culture laboratory the proportion approaches 50/50. Nematodes seem to live mainly in the first few centimeters of the algal mats that cover the microbialites, feeding on the bacteria abundant in these mats.
The team argues that these organisms could become valuable bioindicators. As they are sensitive to changes in salinity, water quality and sediment chemistry, they can function as a “early warning system” in an ecosystem under strong human pressure — and where a small number of species manage to persist.
Furthermore, because they are associated with microbialites, central structures in the production of energy and food in the lake, any ecological interaction involving these nematodes could have chain effects throughout the Great Salt Lake system.
