Analysis reveals new species in Smaug’s group of lizards

Smaug swazicus, a girdled lizard whose range is mainly in the country of Eswatini, is the ninth species to join a genus named after the fearsome dragon in “The Hobbit”. Credit: Edward Stanley

Smaug, the mortal dragon in JRR Tolkien’s “The Hobbit”, has few living relatives. With dense alligator-like armor, these small, actual dragon lizards are rock crevice recluses mostly confined to the mountain peaks of southern Africa.

Today, herpetologists Michael Bates, curator at the National Museum of South Africa in Bloemfontein, and Edward Stanley of the Florida Museum of Natural History discovered a ninth species of dragon lizard in the genus Smaug, previously mistaken for a species of similar, S. barbertonensis.

The new species, a heavily plated dark brown lizard with pale yellow bands, has been named Smaug swazicus, or Swazi dragon lizard, in honor of the country of Eswatini, where most of the range of the species. Up to 13 inches from muzzle to tip of tail, S. swazicus is an unusually large lizard for the region.

“In terms of mass and recorded total length, Smaug swazicus may be the largest southern African lizard species described since the western giant plated lizard, Matobosaurus maltzahni, 82 years ago,” Bates said.

While species in the genus Smaug, also known as girdled lizards, may have scaled-down versions of the shield-like scales and sword-like teeth of their fearsome namesake, they have gentle dispositions, Stanley said. .

“These are just small reservoirs,” said Stanley, who is also director of the Florida Museum’s Digital Discovery and Dissemination Lab. “They hide in rock crevices and spend a lot of their energy and effort just being spiny and inedible, so they don’t have to fight.”

Stanley led a group of scientists who named the genus Smaug in 2011, and he was instrumental in analyzing its species. “Smaug,” he explained, comes from the German word “smugan,” which means “to squeeze through a hole.” These lizards are also found near the Drakensberg Mountains in South Africa, Afrikaans for “dragon mountains”.

Here Come Dragons: Analysis Reveals New Species in Smaug's Lizard Group

Belted lizards of the genus Smaug are heavily armored with bony plates called osteoderms. But despite their fierce appearance, they have gentle dispositions. Credit: Edward Stanley

While Africa has an enormous diversity of lizards, the girdled lizards are the only family exclusive to mainland Africa and, due to their crevice-dwelling lifestyle, are often restricted to specific habitats. As a result, Stanley said stricter conservation strategies may be needed for some Smaug species.

S. barbertonensis already had a relatively small range, but that’s obviously before it was split in half when S. swazicus was discovered,” Stanley said. “So although barbertonensis was not of concern previously, it now has a range of about 200 square miles,” an area less than the size of Chicago.

Attached to rock-filled habitats at high altitudes, dragon lizards could already be feeling the effects of global warming, Stanley said. Securing rock crevices to hide in could become difficult as dragon lizards crawl to higher elevations in search of lower temperatures.

“These creatures have evolved brilliantly for their environment. If nothing is done to protect them, we could lose 20 million years of evolution in 50 years,” he said. “The important thing is that you have to characterize and identify the animals before you can protect them. You have to know what you have before you can come up with a plan to protect it.”

But finding lizards in southern Africa can be daunting: Stanley and his fellow researchers have had to dodge everything from mambas to unexploded explosives. When the team members extended their search to well-shaded rocks on a military base, they were accused of being gold diggers, thieves and pet dealers.

“We had to spend the whole morning explaining, ‘No, we’re not here for that – we’re really just here to try to find lizards on your military base,'” Stanley said. “And actually, because the range was so sparsely populated, the lizards we found there were quite friendly. It was a strange experience to have spent so long looking for them and then to enter this kind of garden where they would run around your lap and jump into your arms.”

Stanley’s next confrontation with the new species was not deep in the South African escarpment. He said he recognized the species from his time at the American Museum of Natural History, where there was a jar of unidentified specimens from the early 1980s pet trade in the herpetology collection.

Here Come Dragons: Analysis Reveals New Species in Smaug's Lizard Group

Species of the genus Smaug have been particularly difficult to distinguish from each other. Researchers used a combination of traditional approaches, DNA analysis and CT scans to identify and describe Smaug swazicus. Credit: Edward Stanley

“That’s the good thing about museums, isn’t it? It’s not like these animals are sitting underground, never seen before. Often they just hide in plain sight,” did he declare.

To differentiate between similar-looking species, Stanley and Bates relied on traditional approaches based on physical characteristics, computed tomography and DNA analysis, a process he likened to sorting candy.

“Let’s say you have different types of candies that you need to sort by type,” Stanley said. “You start by visually sorting all your M&M’s into one pile and your Mike and Ike into another.”

Next comes the DNA analysis, i.e. the taste test.

“So you taste your candies, and you find that there’s a proportion of M&Ms that you’ve sorted that are actually Skittles, and then you notice that instead of an ‘M’, they actually have a little ‘S’ on it,” Stanley said. “Now you can pull them out and say, ‘Oh, I actually have three candies.'”

The new species of dragon lizard can be compared to the Skittles, Stanley said, similar in appearance to S. barbertonensis, but with slight genetic differences that show it is more closely related to another species of dragon lizard, S. warreni. The analysis also allowed Stanley and Bates to analyze minor physical differences that other researchers originally attributed to individual variation and helped explain why Bates’ previous examination of museum specimens revealed three distinct color patterns in dragon lizards.

Stanley said he couldn’t rule out the possibility that other species in the group are waiting to be discovered.

“Even now, in this well-worked group in these highly populated countries of South Africa and Eswatini, which have had many herpetologists working for hundreds of years, there are still some interesting discoveries to be made,” did he declare. “That’s the biggest part of the story for me is that there are awesome animals that aren’t described.”


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More information:
Michael F. Bates et al, A taxonomic review of southeastern dragon lizards of the Smaug warreni (Boulenger) species complex in southern Africa, with the description of a new species (Squamata: Cordylidae), PeerJ (2020). DOI: 10.7717/peerj.8526
Journal information:
PeerJ


Provided by Florida Museum of Natural History


Quote: Behold Dragons: Analysis Reveals New Species in Smaug’s Lizard Group (2020, March 25) Retrieved January 22, 2022 from https://phys.org/news/2020-03-dragons-analysis-reveals- species-smaug.html

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