Eukrohnia hamata is a species of arrow worm, transparent marine invertebrates belonging to the phylum Chaetognatha.

Characterized by its unique morphology and adaptation for life in the deep-sea environment, this planktonic predator is widely distributed throughout the world's oceans, and plays an important role in marine ecosystems.

[2] It exhibits vertical migration, ascending towards the surface at night to feed and descending to deeper depths during the day.

[4] This species lives in miso-bathypelagic zones of the tropical and subtropical oceans, whereas in the sub-arctic and sub-Antarctic regions, it gradually rises to the epipelagic layers.

[6] The chaetognath Eukrohnia hamata dominates in terms of carnivorous zooplankton abundance in the meso- and bathypelagic zones.