To calculate the body size of the supershark without a complete specimen, lead researcher John Maisey, a curator of paleontology at the American Museum of Natural History in New York City, and his colleagues had to get creative.
So they looked to the dimensions of other complete specimens of ancient sharks known as ctenacanthiforms, which are a group of ancient sharks that lived during the Carboniferous period (It's likely supershark is also a ctenacanthiform, but its true identity will emerge only once other supershark remains, such as teeth and fin spines, are found, the researchers said.) The skulls of these ctenacanthiforms accounted for roughly 10 percent of the sharks' entire body length, the researchers found.
If the Texas supershark shared the same proportions, its roughly 31.5-inches-long (80 centimeters) skull suggests that its body was likely more than 26 feet long, Maisey said. The other supershark they discovered likely measured about 18 feet (5.5 m), Maisey said.
Further research is needed to determine whether the Texas supershark specimens represent a known species, such as Glikmanius occidentalis, or a species that has yet to be discovered, Maisey said. But the newly found shark's close relative, the ancient shark from Scotland (Goodrichthys eskdalensis), suggests that this group of sharks had successfully dispersed across large distances. [Dangers in the Deep: 10 Scariest Sea Creatures]
The conference held another gem for shark enthusiasts. During a dig in a New Mexico quarry, John-Paul Hodnett, a graduate student of biology at Saint Joseph's University in Philadelphia, discovered a nearly complete fossilized shark that also dates to about 300 million years ago.
The specimen, a female, measures about 0.6 feet (2 m) long and sports teeth that "are actually brand-new to science," Hodnett told Live Science. "We've never seen this type of tooth before." He plans to analyze the teeth in an upcoming study, he added.
That fossil is so complete that studying it may help researchers better describe ctenacanths, a group of ancient sharks, he said.
"There's a lot of missing data," Hodnett said. "My advisor is always saying if you can't find data, go out digging."
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