A new species of hammerhead shark has been discovered, and its namesake is the late Paul G. Allen, the co-founder of Microsoft and a well-known champion for marine conservation who played a significant role in protecting ocean ecosystems through his many philanthropic efforts. Although Allen passed away in 2018, his legacy continues through the foundation’s ongoing support for shark conservation and marine health. The shark, now formally named Sphyrna alleni, had long been hidden in plain sight from the science world due to its striking resemblance to the bonnethead shark (Sphyrna tiburo), making it difficult to differentiate until scientists took a closer look.
Bonnethead sharks are the smallest members of the hammerhead shark family, distinguished by their unique, shovel-shaped heads. They are typically found in shallow, warm coastal waters of the Atlantic Ocean and Gulf of Mexico, ranging from the United States to Brazil. Relatively small, they usually grow to about 3 to 4 feet in length, and are known for their diet, which includes a significant amount of seagrass—making them one of the few sharks known to be omnivorous. These sharks are important to marine ecosystems, helping control prey populations and contributing to the health of seagrass beds.
The discovery was led by a team of researchers from Florida International University, including Dr. Cindy Gonzalez, the lead author of the study published in Zootaxa. The research team, initially led by FIU’s Dr. Demian Chapman, Director of Mote Marine Laboratory’s Center for Shark Research, worked to uncover the differences between Sphyrna alleni and its lookalike, the bonnethead shark. “DNA analyses provided the first clue that the bonnethead sharks, as we knew them, were at least two species in the Atlantic and not one,” said Chapman in a press release. “But DNA alone is not enough to define a species, so we put a team together to look at specimens and see if there were any physical differences as well.”
Gonzalez, a Colombian marine ecologist, was no stranger to bonnethead sharks, having studied them during her master’s research in Panama in 2015. Her work hinted at the existence of a new species, and together with Chapman, they formed a research plan to fully document it. Latin America is known to be a global hub for small hammerhead shark species, and Sphyrna alleni ranges from Belize to Brazil. Given the shark’s frequent presence in Belizean waters, it’s also commonly called the shovelnose shark, a name given to it by local fishers.
According to Gonzalez, the discovery of the shovelnose shark was a collaborative effort between scientists and the Belizean fishing community: “The work to identify and document this new species was truly a community endeavor and involved a team of scientists and Belizean shark fishers. The fishers and their families became very invested in this process, helping me in collecting tissue samples for genetics and taking hundreds of measurements of these sharks. […] These fishers are deeply knowledgeable and inquisitive about marine-life, so it was a joy to work alongside them.” Unfortunately, progress on the project was delayed when the COVID-19 pandemic hit, halting international travel and forcing the research to continue under challenging conditions. Undeterred, Gonzalez set up a makeshift lab in her apartment, working to measure and analyze the collected specimens. She eventually identified differences in the sharks’ head shapes and the number of vertebrae, as well as confirming its unique DNA profile, formally distinguishing Sphyrna alleni from its bonnethead relative.
Small hammerhead sharks like Sphyrna alleni have long been misidentified in fisheries across the region, which has led to overfishing and population declines. “It is imperative to study and protect small hammerhead shark species as they are unique to the American continent and have been extirpated, overfished, and misidentified in fisheries,” Gonzalez said. “At the same time, these sharks have played a critical role in shaping the culture and economy of many local communities in many Latin American countries, so it is important to work hand-to-hand with the fishermen on conservation efforts.”
Belize offers a glimmer of hope for this new discovery’s future. The country has implemented strong shark conservation measures, including banning gillnets and working closely with fishing communities to manage shark catches. These proactive steps may be the key to protecting the shovelnose shark from extinction. “It’s tragic that we have only just recognized that this species exists, and we are already running against the clock to prevent its extinction,” Chapman said. But with continued conservation efforts, there is still hope that this newly named species can be preserved for future generations.
