A new species of reef fish is a real head turner.
Last year while surveying a remote coral reef about 130 meters below the surface of the Atlantic Ocean, ichthyologists Luiz Rocha and Hudson Pinheiro spotted a radiant fish hiding in a drab rock crevice.
“It was like finding a bright emerald in a coal mine,” recalls Pinheiro.
The fish, with its electric-pink-and-yellow body and bright green fins, was so mesmerizing, “it made us completely ignore a massive [shark] that was hovering over our heads,” Rocha says.
SURPRISE! Despite the exclamations of their fellow diver, Luiz Rocha and Hudson Pinheiro remained oblivious to a sixgill shark, up to 3 meters long, that snuck up on them as they observed a new species of deep-reef fish about the size of a car key (roughly 6 centimeters).
Back in the lab, Claudia Rocha analyzed the fish’s DNA. Those results combined with the observation of a few distinguishing characteristics — a longer spine here, an extra fin ray there — confirmed the fish as a new species, the trio of California Academy of Sciences researchers report September 25 in Zookeys. Due to its hypnotic beauty, they named the fish Tosanoides aphrodite, a nod to the ancient Greek goddess Aphrodite.
T. aphrodite belongs to the same fish group as similarly psychedelic reef inhabitants known as Anthiadinae, but its closest known relatives live over in the Pacific — including a Hawaiian species named in 2016 after President Barack Obama.
The new species turned up in a reef by St. Paul’s Rocks, a series of mid-Atlantic islets about 1,000 kilometers from Brazil. The area’s extreme isolation could help explain why so many of its species aren’t found elsewhere. Still, deep reefs remain understudied habitats, and T. aphrodite or its relatives could be hiding out in other deep Atlantic reefs (SN Online: 7/19/18).