Northern Cutthroat Eel
Synaphobranchus kaupii
- Least concern
- Card rarity: Common
- Fish

The Kaup's arrowtooth eel (Synaphobranchus kaupii), also known as the Kaup's cut-throat eel, the Gray's cutthroat, the Longnosed eel, the Northern cutthroat eel, or the Slatjaw cutthroat eel) is an eel in the family Synaphobranchidae. It was described by James Yate Johnson in 1862. It is a marine, deep water-dwelling eel which is known from the Indo-Western Pacific and eastern and western Atlantic Ocean, including the Faroe Islands, Iceland, Cape Verde, the Western Sahara, Nigeria, Namibia, South Africa, Greenland, France, Saint Pierre and Miquelon, the United Kingdom, Ireland, the Philippines, Portugal, Spain, the Bahamas, Brazil, Canada, Cuba, Japan, Australia, Mauritania, Morocco, and Hawaii. It dwells at a depth range of 120 to 4,800 metres, most often between 400 and 2,200 metres, and inhabits the upper abyssal zone on the continental slope.
Classification
- Class
- Actinopterygii
- Order
- Anguilliformes
- Family
- Synaphobranchidae
- Genus
- Synaphobranchus