Gray Unicornfish

Naso caesius

Fish
IUCN: Least concern

Usual depth6–20 m
Water temperature20–29 °C
Best monthsApril, May, and October
How commonOccasional

Photo credit: (c) amfstocker, some rights reserved (CC BY) · CC BY · iNaturalist

About this species

Naso caesius, the grey unicornfish or silverblotched unicornfish, is a species of marine ray-finned fish belonging to the family Acanthuridae, the surgeonfishes, unicornfishes and tangs. This species occurs in the Indo-Pacific region.

Text from the Wikipedia article “Naso caesius”, licensed CC BY-SA 4.0. Read the article

Where and when

Where it has been recorded

Worldwide

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Best months

Worldwide (open data)

January: 23 records
February: 17 records
March: 28 records
April: 52 records
May: 81 records
June: 25 records
July: 38 records
August: 50 records
September: 49 records
October: 66 records
November: 13 records
December: 3 records

Depth and water temperature

Depth

Mostly recorded at 6–20 m · Deepest record: 61 m

0–10 m: 198 records
10–20 m: 109 records
20–30 m: 28 records
30–40 m: 1 records
40–50 m: 1 records
50–60 m: 11 records
60–70 m: 2 records

Water temperature

Recorded in surface water of 20–29 °C

20–22 °C: 1 records
22–24 °C: 4 records
24–26 °C: 39 records
26–28 °C: 119 records
28–30 °C: 250 records

Photos

Names and classification

English: Gray Unicornfish, Grey Unicornfish

Names in 2 more languages

Spanish: Pez Unicornio Gris
Japanese: Yumiharitenguhagimodoki, ユミハリテングハギモドキ

Similar species

Sleek unicornfish
Naso hexacanthus
Orangespine unicornfish
Naso lituratus
Blue-spine nosefish
Naso unicornis
White margin unicornfish
Naso annulatus
Humpback unicornfish
Naso brachycentron
Spotted unicornfish
Naso brevirostris

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).
476 open-data records from 1982 to 2018.
Species data updated November 4, 2026.

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