An infrequently collected supergiant of the sea is not as rare as previously thought, according to researchers from The University of Western Australia.
Dr Paige Maroni, from UWA's School of Biological Sciences, was lead author of the study published in Royal Society Open Science.
The world's largest amphipod, alicella gigantea, inhabits depths of the lower abyssal ( 3,000 to 6,000 metres) and upper hadal zones (6,000 to 11,000 metres).
"Historically, it has been sampled or observed infrequently relative to other deep-sea amphipods, which suggested low population densities," Dr Maroni said.
"And, because it was not often found, little was known about the demography, genetic variation and population dynamics with only seven studies published on DNA sequence data."
The study looked at 195 records of the giant amphipod from 75 locations across the Pacific, Atlantic and Indian oceans with a depth range of 3,890 to 8,931 metres.
Specimens were collected from nine trenches and three fractures zones from the Pacific and Indian oceans, which confirmed distribution of the species was vast.
"As exploration of the deep-sea increases to depths beyond most conventional sampling, there is an ever-growing body of evidence to show that the world's largest deep-sea crustacean is far from rare," Dr Maroni said.
Researchers used two mitochondrial and one nuclear gene to examine the spatial relationship of the population around the world.
The results identified clear genetic relationships between all specimens collected from all locations in the ocean.
The findings suggest the species may inhabit around 59 per cent of the world's oceans, indicating that the infrequently collected supergiant is widely distributed and has an exceptional global range.
"The advancements in next-generation sequencing technologies and an increase in deep-sea exploration will allow research into the evolution of hadal amphipods to grow rapidly in the coming decades," Dr Maroni said.
"These developments will help reveal further insights into hadal biodiversity, pressure adaptations and the evolutionary history of life in this zone."
