Solvin Zankl / Pacific hatchetfish (Argyropelecus affinis) portrait

David Shale / Greater silver hatchet fish (Argyropelecus gigas) Mid-Atlantic Ridge, North Atlantic Ocean

Norbert Wu / Viperfish (Chauliodus sp) chasing Hatchetfish (Sternoptyx sp) deep sea

David Shale / Deep sea Hatchet fish {Sternoptychidae} Atlantic ocean

David Shale / Greater silver hatchet fish (Argyropelecus gigas) head profile, Mid-Atlantic Ridge, North Atlantic Ocean

David Shale / Ventral view of Hatchet Fish {Argyropelecus hemigymnus} from 2666 - 0m, Mid-Atlantic Ridge, North Atlantic Ocean

David Shale / Close up of abdomen of Greater silver hatchet fish (Argyropelecus gigas) showing ventral light organs, Mid-Atlantic Ridge, North Atlantic Ocean

David Shale / Greater silver hatchet fish (Argyropelecus gigas) Mid-Atlantic Ridge, North Atlantic Ocean

David Shale / Hatchet Fish {Argyropelecus hemigymnus} from 2666 - 0m, Mid-Atlantic Ridge, North Atlantic Ocean

Jane Burton / Marbled hatchetfish {Carnegiella strigata} resting at surface, captive, tropical

Jane Burton / Marbled hatchetfish {Carnegiella strigata} resting at surface amongst floating water fern {Salvinia sp} captive, tropical

Solvin Zankl / Deep-sea hatchetfish {Argyropelecus olfersi} Atlantic ocean

Solvin Zankl / Juvenile deepsea Hatchetfish {Argyropelecus olfersi}, Atlantic ocean

David Shale / Ventral view of Hatchetfish {Argyropelecus hemigymnus} from the Mid-Atlantic Ridge, 400 - 500m

David Shale / Hatchetfish {Argyropelecus hemigymnus} from the Mid-Atlantic Ridge, 400 - 500m

David Shale / Ventral view of Hatchet fish {Sternoptychidae / Argyropelecus hemigymnus} Atlantic

Peter Scoones / Hatchetfish shoal, Indo-Pacific

Solvin Zankl / Hatchetfish (Maurolicus walvisensis) close up of photophores beneath its body, emitting bioluminescent light. This glow, directed downward through light-guides, likely serves as counterillumination vi...

Solvin Zankl / Hatchetfish (Maurolicus walvisensis) ventral view portrait, showing photophores beneath its body, emitting bioluminescent light. This glow, directed downward through light-guides, likely serves as cou...

Solvin Zankl / Deep-sea hatchetfish (Maurolicus walvisensis) portrait, showing bioluminescent organs along the underside of its body. These fish inhabit the mesopelagic zone of the open sea, typically at depths of 1...