Hair-finned Filefish

Paramonacanthus oblongus

Fish
IUCN: Least concern

Usual depth22–54 m
Water temperature20–29 °C
Best monthsSeptember and October
How commonOccasional

All species

Where and when

Where it has been recorded

Worldwide

Loading the map

Best months

Worldwide (open data)

January: 52 records
February: 38 records
March: 3 records
April: 20 records
May: 4 records
June: 30 records
July: 8 records
August: 56 records
September: 97 records
October: 99 records
November: 24 records
December: 20 records

Depth and water temperature

Depth

Mostly recorded at 22–54 m · Deepest record: 147 m

0–10 m: 2 records
10–20 m: 17 records
20–30 m: 122 records
30–40 m: 131 records
40–50 m: 71 records
50–60 m: 33 records
60–70 m: 9 records
70–80 m: 7 records
80–90 m: 8 records
90–100 m: 0 records
100–110 m: 0 records
110+ m: 8 records

Water temperature

Recorded in surface water of 20–29 °C

18–20 °C: 1 records
20–22 °C: 0 records
22–24 °C: 7 records
24–26 °C: 31 records
26–28 °C: 395 records
28–30 °C: 17 records

Names and classification

English: Hair-finned Filefish, Japanese Leatherjacket

Names in 2 more languages

Japanese: Yosogi, ヨソギ
Korean: 새양쥐치

Other scientific names: Monacanthus oblongus, Stephanolepis oblongus

Similar species

Hair-finned Leatherjacket
Paramonacanthus choirocephalus
Dusky Filefish
Paramonacanthus otisensis
Paramonacanthus curtorhynchos
Hairfinned leatherjacket
Paramonacanthus japonicus
Paramonacanthus cryptodon
wedgetail filefish
Paramonacanthus frenatus

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.
Conservation status as published by GBIF (IUCN Red List).
453 open-data records from 1931 to 2023.
Species data updated November 5, 2026.

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