Oarfish Identification Guide

Key identification features

• Extremely elongated, ribbon-like, laterally compressed silvery body
• Small head with a tiny, near-toothless mouth
• Bright red dorsal fin running the entire length of the body, with elongated crest-like rays above the head
• No scales; skin covered in a silvery guanine layer
• Long, paddle-tipped pelvic fins; can exceed 26 feet (8 m)

Common look-alikes

• Ribbonfish (Trachipterus spp.) are shorter and deeper-bodied, and lack the oarfish's continuous red dorsal crest extending over the head.
• The closely related Regalecus russelii looks nearly identical and is mainly distinguished by fin ray counts and its Pacific range versus the Atlantic-based R. glesne.
• True eels lack the vivid red dorsal fin and the unscaled, silvery skin characteristic of the oarfish.

Where you'll see one

Oarfish live in the open ocean's mesopelagic zone, roughly 650-3,300 feet (200-1,000 m) deep, in temperate to tropical seas worldwide. They are rarely observed alive at the surface and are most often encountered washed ashore or filmed by deep-sea cameras.