Ribbon sawtail fish

Idiacanthus fasciola

Fish
IUCN: Least concern

Usual depth55–1,372 m
Water temperature6–30 °C
Best monthsApril and November
How commonOccasional

About this species

The ribbon sawtail fish, Idiacanthus fasciola, is a barbeled dragonfish of the family Stomiidae, found around the world at depths over 500 m (1,640 ft) between latitudes 40° N and 54° S. Length is up to 38 cm (15 in) in general for the female, and 15 cm (5.9 in) for the male. The males of this species are developed to a lesser degree, as usual for Idiacanthus. While female specimen have a dark brown to black colour, males are usually of a lighter colour between dark brown to pale. The larval form, which has eyes on periscopic stalks, was originally identified under the invalid name Stylophthalmus paradoxus. Its diet is carnivorous, preying on living and dead fish or meat.

Text from the Wikipedia article “Ribbon sawtail fish”, 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: 7 records
February: 11 records
March: 22 records
April: 47 records
May: 31 records
June: 20 records
July: 11 records
August: 14 records
September: 29 records
October: 41 records
November: 76 records
December: 18 records

Depth and water temperature

Depth

Mostly recorded at 55–1,372 m · Deepest record: 4,525.5 m

0–10 m: 16 records
10–20 m: 0 records
20–30 m: 1 records
30–40 m: 3 records
40–50 m: 0 records
50–60 m: 10 records
60–70 m: 6 records
70–80 m: 6 records
80–90 m: 9 records
90–100 m: 5 records
100–110 m: 5 records
110+ m: 209 records

Water temperature

Recorded in surface water of 6–30 °C

4–6 °C: 1 records
6–8 °C: 1 records
8–10 °C: 1 records
10–12 °C: 3 records
12–14 °C: 7 records
14–16 °C: 6 records
16–18 °C: 16 records
18–20 °C: 20 records
20–22 °C: 70 records
22–24 °C: 67 records
24–26 °C: 69 records
26–28 °C: 32 records
28–30 °C: 56 records

Names and classification

English: Ribbon sawtail fish, Ribbon sawtailfish, Black Dragon, black dragonfish, deepsea stalkeye fish, Gleaming-tailed Seadragon, Ribbon Sawtail, ribbon sawtail fish, ribbon sawtailfish, Sawtailfish, Serpent Black Dragonfish, Serpent Dragon, Stalk-eyed Marvel

Names in 4 more languages

Spanish: dragón negro
French: Idiacanthe ruban
Japanese: Nan-yomitsumatayariuo, ナンヨウミツマタヤリウオ, ミツマタヤリウオ
Simplified Chinese: 奇棘魚, 巨口魚

Other scientific names: Bathyophis ferox, Idiacanthus ferox, Stylophthalmus paradoxus

Similar species

Gunther's boafish
Stomias affinis
Grimaldi's loosejaw
Aristostomias grimaldii
Loosejaw
Aristostomias lunifer
Manyray Loosejaw
Aristostomias polydactylus
Strangemouth Loosejaw
Aristostomias xenostoma
Twinlobe Snaggletooth
Astronesthes bilobata

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).
1,049 open-data records from 1902 to 2024.

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