Researchers have discovered a whole new evolutionary branch on the deep-sea floor, having found an entirely new superfamily, and 24 new deep-sea species on the central Pacific’s seafloor.

These amphipod creatures – small crustaceans – were found on the seabed, in the Clarion Clipperton Zone. Their formal identification was published today in the scientific journal ZooKeys.

While thousands of new species are named every year, a new superfamily suggests a fundamental gap in our previous understanding of how certain creatures evolved and diversified in the deep ocean.

Alongside identifying a new family and superfamily, scientists also discovered certain amphipods were living much deeper than previously thought possible.

Scientists also discovered the first molecular barcodes, or DNA “fingerprint” for these rare species – expanding our knowledge of the creatures, and meaning their presence is able to be monitored much more easily

Led by Dr Anna Jażdżewska from the University of Lodz and Tammy Horton, National Oceanography Centre, 16 experts and early-career scientists came together for a week-long workshop dedicated to describing new amphipod species from the CCZ.

Dr Horton said: “To find a new superfamily is incredibly exciting, and very rarely happens so this is a discovery we will all remember.

“With more than 90% of species in the CCZ still unnamed, each species described is a vital step towards improving our understanding of this fascinating ecosystem,” she added.

The samples, vessel and funding were provided by The Metals Company – the same deep-sea mining organisation who have earmarked the CCZ for polymetallic nodule extraction

A wealth of scientific research details the destruction deep-sea mining would have on an ecosystems we still know very little about.

Last week, the 31st International Seabed Authority drew to a close. No mining was approved, and the long-delayed Mining Code – the regulatory rulebook that would need to be in place before any commercial extraction could legally proceed – remained both unfinished and deeply contested.

“Describing the species encountered during these studies is a critical step in documenting the rich biodiversity of the CCZ, enabling us to communicate effectively about the fauna,” Dr Horton said.