Media release

From: The Royal Society

Giants of the deep - The supergiant amphipod, Alicella gigantea, may inhabit over half of the world's oceans

Alicella gigantea, the world’s largest amphipod, has long been considered rare due to infrequent sightings. However, new research reveals that this deep-sea giant is far more widespread than previously thought. By analyzing 195 records from 75 locations worldwide, scientists found that A. gigantea inhabits around 59% of the world’s oceans. Using genetic data from mitochondrial and nuclear DNA, the study explores its global distribution and evolutionary history. These findings challenge past assumptions, showing that while rarely collected, A. gigantea is not rare—it is a remarkably widespread deep-sea species thriving across vast and extreme ocean depths.

Giants of the deep – A rarely-sighted “supergiant” crustacean may inhabit over half the world’s deep oceans. Researchers analysed nearly 200 records of Alicella gigantea, from 75 locations on the seabed. They predict this single species is thriving at vast and extreme depths in 59% of oceans. Reaching lengths of up to 34cm, A. gigantea is the largest-known species of amphipod a crustacean group related to isopods (woodlice) and more-distant decapods (shrimp and lobsters).