The supergiant amphipod Alicella gigantea may inhabit over half of the world's oceans

Area of Science:

• Marine Biology
• Deep-Sea Ecology
• Genetics

Background:

• Alicella gigantea, the world's largest amphipod, inhabits abyssal and hadal zones.
• Historically considered rare due to infrequent sampling and limited genetic data.
• Previous studies suggested low population densities and limited distribution.

Purpose of the Study:

• To reassess the distribution and rarity of Alicella gigantea.
• To investigate the species' population dynamics and global range.
• To explore the historical distribution of A. gigantea throughout geological time.

Main Methods:

• Compiled 195 records of A. gigantea from 75 global locations.
• Analyzed DNA sequences from two mitochondrial genes (16S, COI) and one nuclear gene (28S).
• Examined distribution patterns across all oceans.

Main Results:

• A. gigantea occupies approximately 59% of the world's oceans.
• The species is widely distributed, contrary to previous assumptions of rarity.
• Genetic analysis supports a broad geographic range.

Conclusions:

• Alicella gigantea is not a rare species but a widely distributed deep-sea amphipod.
• The species possesses an exceptional global range, inhabiting vast deep-sea areas.
• Further research on deep-sea biodiversity is warranted given the extensive range of A. gigantea.