Scientists Found Two Bizarre New Sea Spiders. One Has Three Lips and Red Eyes
... and the other is crawling with microscopic parasites.
by Mihai Andrei · ZME ScienceBetween the Canadian province of British Columbia and the U.S. state of Washington, the Salish Sea has been hiding two tiny oddities in plain sight.
Researchers have described two sea spiders previously unknown to science — the first new species formally described from this rich stretch of Pacific Northwest water in almost a century.
Sea spiders are almost always bizarre, and this one has red eyes, hairy-looking feet and a three-lipped mouth. The other is such a poor groomer that microscopic organisms regularly colonize its body. But it’s not just about the creatures themselves. Rather, it’s about what these two sea spiders show: scientists still don’t know nearly enough about some of the small animals living just offshore.
The hairy one
Halloween isn’t for a few more weeks, but these creatures are horrifyingly interesting.
Callipallene pilosuspedes takes the second half of its scientific name from Latin words referring to “hairy feet.” Long, curved spines cover parts of its walking legs. It also has conspicuous red eyes and a short feeding apparatus ending in a tiny triangular mouth divided into three lips and fringed with sensory structures.
Granted, both species are about 1 cm (less than half an inch), but put them under a microscope, and that mouth looks considerably more menacing than an animal this small has any right to look.
But perhaps its strangest feature sits closer to its head. Sea spiders possess specialized appendages called ovigers. In males, these usually help carry eggs. In C. pilosuspedes, researchers watched the animal bend its highly mobile ovigers around its own walking legs and pull comb-like spines across them.
RelatedPosts
Exotic extreme microbes played a role in Earth’s early atmosphere
The trap-jaw is the fastest in the world — and it independently evolved several times in ants
The World’s Oldest Known Ant Is A 113-Million-Year-Old Hell Ant with Scythe Jaws
The Human Mind May Be No Match for Modern Life
In other words, this sea spider appears to carry its own grooming equipment.
×
Get smarter every day...
Stay ahead with ZME Science and subscribe.
Daily Newsletter
The science you need to know, every weekday.
Weekly Newsletter
A week in science, all in one place. Sends every Sunday.
No spam, ever. Unsubscribe anytime. Review our Privacy Policy.
Thank you! One more thing...
Please check your inbox and confirm your subscription.
The second spider is basically its own ecosystem
The second newcomer is Tanystylum kiixin, pronounced roughly “kee-hin.”
Its name refers to Kiix̣in, the traditional capital of the Huu-ay-aht First Nations on Vancouver Island. Archaeological evidence indicates people occupied the site for almost 3,000 years, and it remains sacred to the Huu-ay-aht today. Researchers named it thusly to honor the population.
Unlike its hairy-footed counterpart, T. kiixin has much smaller, less dexterous ovigers. That seemingly minor anatomical makes a big difference, because these animals often accumulate dirt and debris. Researchers also repeatedly found tiny creatures (protists) living on them, including organisms identified as parasites.
Lead author Cormac Toler-Scott described the result in the UBC release as “an ecosystem within an ecosystem within an ecosystem.” A sea spider living among other marine organisms had, in turn, become habitat for organisms of its own.
Sea spiders were already a weird group
Don’t let the name fool you, sea spiders aren’t really spiders (confusing, I know).
They are pycnogonids, an ancient branch of marine arthropods related to the broader group that includes spiders, scorpions and horseshoe crabs. They live entirely in the ocean and usually spend their lives crawling across the seafloor or over other organisms.
Many have a body plan that borders on the absurd.
Some species have such a tiny central body that major organs extend down into their legs. For others, their digestive tract also branches into the limbs. And they have no lungs or gills. Instead, oxygen passes through their thin outer surface.
Males are also usually the ones saddled with childcare. After mating, they carry developing eggs on their ovigers until the young emerge.
They’re also one of the most poorly understood groups of animals.
The animals that science often overlooks
Toler-Scott and his colleagues collected sea spiders between September 2023 and August 2024 during dives reaching about 18 meters deep.
They sampled sites around Vancouver, Victoria, Quadra Island and the west coast of Vancouver Island near Bamfield. Back in the lab, the team examined the animals with high-resolution scanning electron microscopy and compared their DNA to known sea-spider lineages.
“I was interested in how sea spiders are impacted by climate change and human disturbance, because marine invertebrates in the Salish Sea are particularly at-risk, and I couldn’t find anything,” said lead author Cormac Toler-Scott, who conducted the work as part of his master’s degree in zoology at UBC. “That’s largely because people don’t know much about what species exist here and what their lifestyle is.”
They studied seven species in detail.
Five were already known to science but badly needed modern descriptions. The remaining two became T. kiixin and C. pilosuspedes.
It’s unlikely that the researchers just happened to come across two unique and new species. The Salish Sea probably holds more surprises, just as wonderfully bizarre as these two.
The peer-reviewed article can be read here.