At a depth between 3.7 and 6.8 miles, the world’s hadal zones—named after Hades, the Greek god of the underworld—are the deepest parts of the oceans. Marine biologists have now uncovered a predator adapted to thrive in these pitch-black, crushingly high-pressure depths.
Researchers from Woods Hole Oceanographic Institution (WHOI) and Instituto Milenio de Oceanografía (IMO) in Chile have identified one of the first large, active predatory amphipods ever documented in the world’s hadal zones. Their findings, detailed in a November 27 study published in the journal Systematics and Biodiversity, reveal a never-before-seen species from an iconic yet mysterious region once thought uninhabitable.
While the word “predatory” likely evokes images of large, fearsome creatures, the Dulcibella camanchaca is a shrimp-like crustacean less than 1.58 inches (4 centimeters) long that belongs to the same classification as beach sandhoppers, according to the study. It does, however, have specialized raptorial appendages it uses to capture prey—primarily smaller amphipods in the Atacama Trench. Also known as the Peru–Chile Trench, it runs along the coast of the two countries and is over 4.97 miles (8 kilometers) deep in certain areas.
“Dulcibella camanchaca is a fast-swimming predator that we named after ‘darkness’ in the languages of the peoples from the Andes region to signify the deep, dark ocean from where it predates,” Johanna Weston of WHOI, who co-led the study, said in a WHOI statement.
D. camanchaca was discovered during the 2023 Integrated Deep-Ocean Observing System (IDOOS) Expedition led by IMO scientists. The team collected four amphipods of the species via a lander vehicle (a mechanical platform that shuttles equipment from the ocean’s surface to its depths) which brought them up to the water’s surface from a depth of 4.91 miles. The researchers froze four crustacean specimens onboard the ship before conducting morphological and genetic analyses at the Universidad de Concepción.
“Most excitingly, the DNA and morphology data pointed to this species being a new genus too, emphasizing the Atacama Trench as an endemic hotspot,” Weston added. In taxonomy, genus groups are closely related species, and endemic species are those found exclusively in a specific region.
Although hadal zones might seem uninhabitable, they are far from barren. Dozens of species thrive in these harsh marine landscapes, and every new creature identified provides insight into how these animals evolved to live in such extreme environments, according to the researchers. In fact, the Atacama Trench hosts a particularly unique ecosystem because it is far from other hadal zones.
“This study’s collaborative effort and integrative approach confirmed Dulcibella camanchaca as a new species and highlights ongoing biodiversity discoveries in the Atacama Trench. This finding underlines the importance of continued deep-ocean exploration, particularly in Chile’s front yard,” said Carolina González of IMO, who also co-led the study. “More discoveries are expected as we continue to study the Atacama Trench.”
Ultimately, the researchers highlight that a stronger understanding of deep-ocean ecosystems empowers scientists to better conserve them, particularly from threats such as climate change. It remains to be seen when the next tiny deep-sea predator will shed more light on these mysterious marine regions.
Read the full article here
