09/07/2025
In 2019, marine scientists confirmed something extraordinary: a brand-new species of pocket shark, Mollisquama mississippiensis, discovered in the depths of the Gulf of Mexico. Measuring only about 14 centimeters long, this tiny shark has a surprising ability — it glows in the dark.
The animal was first collected in 2010 during a research trip studying s***m whales. At the time, its significance wasn’t fully understood. It wasn’t until 2013, after closer examination by experts from NOAA and Tulane University, that researchers realized the specimen represented an entirely new species. Their findings were later published in the journal Zootaxa.
What makes this shark so remarkable is its built-in light show. Just behind its gills, it carries pocket-like glands that release a glowing fluid. Scientists believe this bioluminescence could serve as a way to attract prey in the pitch-black ocean or confuse predators. In addition, the shark’s skin is covered with tiny light-producing organs called photophores, giving it an otherworldly glow in the deep sea.
High-tech imaging methods, including CT scans and X-rays, helped researchers confirm the shark’s identity. Compared with related species, Mollisquama mississippiensis has fewer vertebrae, distinctive teeth, and even a structure near its jaw that might act as a pressure sensor, allowing it to navigate the crushing depths where it lives.
This discovery marked only the third known shark species capable of squirting luminous liquid, alongside the taillight shark and another rare pocket shark found in the Pacific. For scientists, finding Mollisquama mississippiensis after decades without new sightings of pocket sharks is a powerful reminder that the oceans still hold countless secrets, waiting in the dark to be uncovered.
