Study offers glimpse of 500-million-year-old sea worm named after 'Dune' monster

A University of Kansas paleontologist has discovered a long-extinct sea worm during excavations in the "Spence Shale Lagerstätte," a fossilized fossil treasure trove. Currently, the discovery has been made public in the journal Historical Biology.

In the High Creek region of the Spence Shale, a geological formation spanning northern Utah and southern Idaho, Rhiannon LaVine, a research associate with the KU Biodiversity Institute and Natural History Museum, was doing fieldwork when she discovered the fossil. Since the early 1900s, the region has gained notoriety for being home to more than 90 different species of Cambrian trilobites and soft-bodied fossils.

LaVine recalled, "I split open one of these pieces of rock one of the last times we were out there and I instantly knew it was something that wasn't typical." "These radial blades that resemble stars or flowers are what we initially notice. I immediately showed it to Julian Kimmig (the principal author). He was confused. The man has stated, "I've never seen anything like that." Paul Jamison, a local who has worked the site for years, was with us when we went exploring. If there is anything within that someone has seen, he has seen it. However, he had missed it.

LaVine spoke with colleagues about the enigmatic fossil after bringing it back to the KU Biodiversity Institute, where it is currently a part of the permanent paleontological collection.

I was displaying it to everyone and requesting their opinions. said LaVine. "Nobody had a thought. We speculated that it may be a wiwaxia, a fairly unusual species from around that period, but the Spence region doesn't have many examples of it. It might also be a scale worm, albeit no authentic scale worms from that era are known. Perhaps it was a young jellyfish, although given its sharp edges and straight lines, it would be strange. So I was unable to receive a reliable response.

The fossil was then subjected to scanning electron microscopy and energy-dispersive X-ray spectroscopy by LaVine and associates from the University of Missouri.

The KU researcher explained, "We mainly wanted to make sure that this was a biological thing because it's possible it could have just been some weird mineral growth." So, the main reason we gave it to them was for that. It is somewhat shorter than the length of a smartphone at around 7 or 8 cm. For that kind of fossil, it's rather large. We were able to undertake the scanning to rule out the possibility that it was merely a mineral growth.

Finally, LaVine and her co-authors were able to identify the fossil as belonging to a hitherto undiscovered species of annelid, a varied phylum that contains around 21,000 species of "segmented worm" that may be found in terrestrial, freshwater, and marine settings all over the world.

Shaihuludia shurikeni is the scientific name given to the species by LaVine, who also co-authored the study revealing the new fossil worm. Frank Herbert's "Dune" novels give the worms on the planet Arrakis the native name Shai-Hulud, while the Japanese term "shuriken" (literally, "throwing star") refers to the form of the blade-like chaetae (the stiff bristles that distinguish many annelids).

LaVine stated, "I've participated in describing species before, but this is the first one I've named. "Actually, I was able to identify its genus, so I guess I can add that to my resume. Because I'm a big ol' nerd and at the time I was getting extremely psyched about the "Dune" movies, it was the first thing that sprang to mind.

Shaihuludia shurikeni is a huge deal, much like the fictional worm of the same name. It's not every day that a new species of Cambrian annelid is described.

Lead author Julien Kimmig is a paleontologist from the State Museum of Natural History in Karlsruhe, Germany. "Annelids are very rare in the Cambrian of North America, and so far we only knew of a single specimen from the Spence Shale," he said.

"The newly discovered annelid Shaihuludia shurikeni is particularly fascinating since it is distinct from other Cambrian annelids in that it possessed some really spectacular chaetae. Because much of the soft tissue is preserved as an iron oxide "blob," which suggests the animal died and was degrading for some time before it was fossilized, the method the fossil is preserved is also very interesting. However, we demonstrate in the research that even with poor preservation, fossils may still be identified.

Burgessochaeta were unexpectedly reclassified as a result of the team's reexamination of a fossilized annelid that had previously been discovered in the Spence Shale. Burgessochaeta had previously only been discovered in a renowned fossil deposit in British Columbia, Canada.

Burgessochaeta is mostly found in the Burgess Shale, according to LaVine. Canadia, which is sort of a wastebasket genus for many of the annelids that emerge out of these types of deposits, was the name of a similar worm that was once discovered in our Spence Shale decades ago.

"For a very long time, no one really looked into it, but when we acquired this one, we looked at the other annelid located there a bit more closely. Perhaps this was a different version of it or somehow connected to it, LaVine speculated. This is the first time the second annelid from the Spence Shale has been described outside of the Burgess Shale, and we found it to be closer to Burgessochaeta.

Both worm species would have lived in an invertebrate-dominated marine habitat that included trilobites, brachiopods, mollusks, and early arthropods. The abundant marine fauna of the mid-Cambrian is renowned.

This revelation makes us consider the depths of time, according to LaVine. "Every animal we are familiar with is present when we glance outside. Now we may stroll by a duck, visit a beach, and observe all the sea life that lives there. We anticipate things somewhat. However, after that, we may use a little of our imagination to speculate about what might have happened a million years ago, or in this case, more than 500 million years ago. How does the ocean seem in such case?

"You're going to see a lot of the same guys, but evolution has made them a little bit alien. It's fascinating to consider that the same piece of land upon which we now stand has witnessed a variety of historical events and environmental conditions over the course of billions of years. Aliens' worlds have existed under our feet.

Provided by University of Kansas