Grey cutthroat eel

Synaphobranchus affinis

Fish
IUCN: Least concern

Usual depth520–1,158 m
Water temperature5–29 °C
Best monthsApril, May, and December
How commonOccasional

About this species

The grey cutthroat eel (Synaphobranchus affinis), is a cutthroat eel. It was originally described by Albert Günther in 1877. It lives a benthic lifestyle, inhabiting the continental slope and global deep waters including near Portugal, Canary Islands, Morocco, Japan, Australia, and others. It is a marine, deep water-dwelling eel which has been found at depths ranging from 300 to 2,300 meters and at temperatures ranging from 3.3 - 11.3 °C. Males can grow to a length of up to 110 centimetres. It is primarily a scavenger, however it also actively hunts small fish and crustaceans.

Text from the Wikipedia article “Grey cutthroat eel”, licensed CC BY-SA 4.0. Read the article

Where and when

Where it has been recorded

Worldwide

Loading the map

Best months

Worldwide (open data)

January: 3 records
February: 12 records
March: 17 records
April: 44 records
May: 57 records
June: 36 records
July: 18 records
August: 41 records
September: 29 records
October: 41 records
November: 43 records
December: 51 records

Depth and water temperature

Depth

Mostly recorded at 520–1,158 m · Deepest record: 3,162 m

0–10 m: 1 records
10–20 m: 0 records
20–30 m: 0 records
30–40 m: 0 records
40–50 m: 0 records
50–60 m: 0 records
60–70 m: 1 records
70–80 m: 0 records
80–90 m: 0 records
90–100 m: 0 records
100–110 m: 4 records
110+ m: 353 records

Water temperature

Recorded in surface water of 5–29 °C

4–6 °C: 1 records
6–8 °C: 0 records
8–10 °C: 0 records
10–12 °C: 2 records
12–14 °C: 12 records
14–16 °C: 11 records
16–18 °C: 30 records
18–20 °C: 62 records
20–22 °C: 138 records
22–24 °C: 40 records
24–26 °C: 67 records
26–28 °C: 54 records
28–30 °C: 25 records

Names and classification

English: Grey cutthroat eel, Gilbert's Synaphobranchid Eel, Grey Cutthroat, grey cutthroat eel, Grey Cut-throat Eel, Grey Cutthroat Eel

Names in 2 more languages

Japanese: Hora-anago, Horaanago, ホラアナゴ
Simplified Chinese: 合鰓鰻, 長鰭合鰓鰻(連鰓鰻)

Other scientific names: Synaphobranchus brachysomus, Synaphobranchus taketae, Synapobranchus affinis

Similar species

Kaup's arrowtooth eel
Synaphobranchus kaupii
Shortdorsal Cutthroat Eel
Synaphobranchus brevidorsalis
Basketwork eel
Diastobranchus capensis
Parasitic eel
Simenchelys parasitica
Atractodenchelys robinsorum
Shortbelly eel
Dysomma anguillare

Sources and credits

Names and taxonomy: WoRMS (CC BY 4.0) and the GBIF Backbone (CC BY 4.0). Photos: iNaturalist observers, each under the licence shown (CC0, CC BY or CC BY-SA).

Depth, temperature, months and maps: records from OBIS and GBIF under CC0 or CC BY.
Descriptions: Wikipedia, licensed CC BY-SA, each linked to its article.
Conservation status as published by GBIF (IUCN Red List).
786 open-data records from 1877 to 2024.
Species data updated October 31, 2026.

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