In a wetland near Mount Gambier in South Australia, Sheryl Holliday crouched in ankle-deep water, camera lens focused on blooming purple orchids a few feet away. Just as Holliday was getting ready to press the shutter, she caught a glimpse of something small jumping out of the frame.
Little did she know on that clear November day, but she had just discovered an entirely new species of peacock spider, a group of unknown Australian jumping spiders known for their vibrant colors and elaborate mating dances.
“I’ve been hunting peacock spiders for three or four years,” said Holliday, an ecological field officer for Nature Glenelg Trust and citizen scientist, but this one looked different. First, its belly was dull and the creature had distinctive orange-and-white facial patterns. (Learn how male peacock spiders use optical illusions to chase mates.)
Intrigued, Sheryl shared her photos on a Facebook page for the peacock spider’s appreciation, which caught the attention of Page administrator and arachnologist, Joseph Schubert, who had never seen one like it before.
The pair made contact, and Holliday collected and sent live specimens to Melbourne, allowing Schubert and colleagues to formally identify the arachnid as maratus nemo, to Nemo, Disney’s heroic clownfish. (The Walt Disney Company is a majority shareholder of National Geographic Partners.)
The Nemo peacock spider, recently described in the magazine Evolutionary Systemis the latest in a flurry of peacock spider discoveries that has taken their known number from just 15 in 2011 to 92 today. (See more photos and videos of newly discovered peacock spiders.)
Schubert, a biologist at Museums Victoria, attributes the boom to the convenience of modern photography, where anyone can quickly snap a photo on their smartphone and upload their findings to social media.
Of course, being popular also helps. The charming mating dance of these rice-grain arachnids has spawned countless viral memes that have made the peacock spider an internet sensation.
Movers and shakers
That doesn’t mean they are easy to find. For most of the year, peacock spiders are brown; only males get their striking colors after they molt in the spring. Combine that with their small size, and it’s no surprise that studying the non-venomous arachnids can be challenging.
That’s why when identifying a new species, Schubert zooms in on the male’s colorings and their mating dance, which is unique to each species, where a male bends and twirls to show off his fitness. When Schubert encouraged a male Nemo to dance for a female in the lab, he was surprised by what he found.
This one person “didn’t lift his belly all the way up like other species, and he doesn’t have those opisthosoma flaps” — which give the spider its famously colorful display — “under the belly. He just has a little brown booty,” explains Schubert. . (Read how peacock spiders get such blue bellies.)
Instead, the male impressed the female by raising his third set of legs and vibrating his abdomen on the ground, generating an audible sound. It’s unknown, he says, whether this is a signature dance of the Nemo peacock spider.
Schubert noted that Nemo’s wetland home is also “very strange” as most other known peacock spiders prefer dry undergrowth.
But peacock spiders always surprise him. In 2020, scientists found one species, Maratus volpei, living in a salt lake. “We’ve learned that we need to be more open to the types of habitats that we look for peacock pins,” Schubert says.
While peacock spiders play a valuable role as predators controlling insect populations, far too little is known about their role in the ecosystem and conservation status, he adds.
A tangled web
“Peacock spiders are excellent because they challenge the prevailing view of spiders as large, hairy and dangerous,” said Michael Rix, chief curator of arachnology and research fellow at Australia’s Queensland Museum, who was not involved in Schubert’s research.
“This really is an excellent example of how interesting, diverse and still understudied Australia’s spider fauna is,” said Rix. (See photos of peacock spiders nicknamed Sparklemuffin and Skeletorus.)
Only about 30 percent of Australia’s invertebrates have been formally documented, and as many as 15,000 species of spiders can still be identified.
Discovering new spiders could also benefit humanity, whether it’s fighting agricultural pests or inspiring new medical treatments, Rix says. Funnelweb spider venom proteins are already being used to develop pain-relieving drugs, as well as treatments for epilepsy, stroke and possibly some cancers.
Meanwhile, arachnid and insect populations are plummeting worldwide. In Australia, habitat loss, wildfires and pesticides can kill entire spider species before we have a chance to find them, Rix warns.
“Essentially, we can’t preserve our biodiversity for future generations,” he says, “if we don’t even know it exists.”