In News:

Rare giant shrimp is more widespread than previously believed; new findings reveal.

About the Species:

• Alicella gigantea is a giant deep-sea amphipod crustacean, growing up to 34 cm in length, making it one of the largest known amphipods.
• Amphipods are shrimp-like organisms; over 10,000 species are known globally, inhabiting a wide range of aquatic environments.

Habitat and Depth Range:

• Inhabits the abyssal (3,000–6,000 m) and hadal zones (>6,000 m) of the ocean.
• Notable sightings include:
  • A 28 cm specimen observed at 5,304 m in the North Pacific.
  • Captures from 6,746 m depth in the Murray Fracture Zone (North Pacific).

Global Distribution:

• Contrary to earlier beliefs, A. gigantea is not rare but is among the most widely distributed deep-sea species.
• Recent analysis compiled 195 records from 75 locations across the Pacific, Atlantic, and Indian Oceans, covering 15 different seafloor features.
• Found in 59% of the world’s oceans.
• The Pacific Ocean is its most significant habitat, with 75% of the seafloor in its suitable depth range.

Genetic Insights:

• Genetic analyses (16S, COI, 28S genes) show low genetic divergence across populations.
• This suggests A. gigantea represents a single, globally distributed species with strong genetic conservation.
• A shared haplotype network across regions indicates minimal genetic differentiation, supporting global connectivity among populations.

Conservation and Research Significance:

• Despite its wide range, A. gigantea remains poorly understood, particularly in terms of population size, ecology, and evolutionary history.
• Only seven studies have sequenced its DNA to date.
• The findings are a significant step toward understanding deep-sea biodiversity, biogeography, and conservation priorities in abyssal ecosystems.