24 new deep-sea species found including a rare new branch of life

The findings, published March 24 in an open-access ZooKeys special issue, represent a major step forward in documenting life in the CCZ. This vast region stretches across six million square kilometers between Hawai'i and Mexico and remains one of the least understood ecosystems on Earth.

The project was led by Dr. Anna Jażdżewska of the University of Lodz (UL) and Tammy Horton of the National Oceanography Centre (NOC). A team of 16 specialists and early-career researchers gathered for a week-long taxonomy workshop in 2024 at UL's Department of Invertebrate Zoology and Hydrobiology, where they focused on identifying and describing amphipod species from the region.

This work contributes to the International Seabed Authority's Sustainable Seabed Knowledge Initiative (SSKI) and its 'One Thousand Reasons' project, which aims to formally describe 1,000 new species by the end of the decade.

Rare Evolutionary Discoveries and New Species Groups

The study revealed several major scientific milestones. In total, the team described 24 new species across 10 amphipod families, including both predators and scavengers.

Among the most significant findings were:

• A newly identified family (Mirabestiidae) and superfamily (Mirabestioidea), representing entirely new branches on the evolutionary tree.
• Two new genera (Mirabestia and Pseudolepechinella).
• The deepest recorded occurrences for several known genera.
• The first molecular barcodes for a number of rare species.

Dr. Tammy 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.

"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."

Global Collaboration Advances Deep-Sea Biodiversity Research

Careful classification, known as taxonomy, is essential for understanding the animals that live in the CCZ. It provides key information about species identity, distribution, and ecological roles within this delicate environment.

Researchers from the National Oceanography Centre described eight of the new species, working alongside collaborators from institutions around the world. These included the University of Lodz, Natural History Museum in London, Canadian Museum of Nature, Earth Sciences New Zealand (NIWA), University of Hamburg, Senckenberg -- Leibniz Institution for Biodiversity and Earth System Research (SGN), and the University Museum of Bergen.

The project also demonstrated how effective coordinated taxonomy workshops can be, offering a faster and more collaborative approach to species discovery.

Anna Jażdżewska, University of Lodz, said: "This was a truly collaborative process that allowed us to achieve the ambitious goal of describing more than 20 species new to science within a year -- something that would not have been possible if each of us worked independently.

"The team's findings provide information that is crucial for future conservation and policy decisions, and it highlights how important it is for this work to continue."

At the current pace of roughly 25 new species described each year, scientists estimate that amphipods in the eastern CCZ could be nearly fully cataloged within the next decade.

How New Deep-Sea Species Get Their Names

Each newly discovered species must be given a scientific name, and researchers often draw inspiration from people, experiences, or even popular culture.

Many of the 24 species received names that reflect personal connections. Co-leads Dr. Tammy Horton and Anna Jażdżewska were both honored with species named after them: Byblis hortonae, Thrombasia ania, and Byblisoides jazdzewskae (respectively).

Dr. Horton also named a species in the new superfamily (Mirabestia maisie) after her daughter, who had long waited to join her siblings in receiving that distinction.

The team also recognized the World Register of Marine Species (WoRMS) by naming Eperopeus vermiculatus in its honor, calling WoRMS a 'wonderful resource for all marine taxonomists'.

Early-career scientists (including students) contributed to the naming process as well, often honoring family members or drawing creative connections between deep-sea life and digital worlds. One species, Lepidepecreum myla, was named for a video game character, with the author noting that both 'are just little arthropods trying to survive in total darkness.'

Language also played a role in naming. The species Pseudolepechinella apricity reflects a sense of warmth and friendship that developed during the workshop.

Dr. Horton revealed: "Apricity means the feeling of the warmth of the winter sun, and it is one of my favorite words. It was very apt to use during the workshop as we discussed our findings in the warmth of the February sun amid the snow of the Polish winter in Lodz. It was certainly fitting to also use it for one of our amphipod discoveries.

"We came together as research colleagues, but the spirit of collaboration and shared experience shone through, so it was important to recognize that in our work."