Blue Cubehead

Cubiceps caeruleus

Fish
IUCN: Least concern

Usual depth50–883 m
Water temperature7–29 °C
Best monthsJune and August
How commonRare

About this species

Cubiceps caeruleus, the blue fathead or cubehead, is a species of driftfish native to the Pacific and Atlantic oceans. It is a pelagic fish that can be found at depths of from 20 to 250 metres. It mostly feeds on salps. This species can reach a length of 25.6 centimetres (10.1 in) TL.

Text from the Wikipedia article “Blue fathead”, 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: 1 records
February: 9 records
March: 15 records
April: 6 records
May: 3 records
June: 28 records
July: 5 records
August: 20 records
September: 5 records
October: 1 records
November: 14 records
December: 6 records

Depth and water temperature

Depth

Mostly recorded at 50–883 m · Deepest record: 1,207 m

0–10 m: 3 records
10–20 m: 1 records
20–30 m: 2 records
30–40 m: 2 records
40–50 m: 0 records
50–60 m: 3 records
60–70 m: 0 records
70–80 m: 1 records
80–90 m: 0 records
90–100 m: 1 records
100–110 m: 2 records
110+ m: 78 records

Water temperature

Recorded in surface water of 7–29 °C

6–8 °C: 7 records
8–10 °C: 7 records
10–12 °C: 1 records
12–14 °C: 12 records
14–16 °C: 16 records
16–18 °C: 35 records
18–20 °C: 14 records
20–22 °C: 7 records
22–24 °C: 23 records
24–26 °C: 0 records
26–28 °C: 2 records
28–30 °C: 2 records

Names and classification

English: Blue Cubehead, Blue fathead, Cubehead

Names in 2 more languages

Spanish: Derivantes, Pez Medusa, Savorines
Japanese: ミナミオキメダイ

Other scientific names: Cubiceps caerulus, Cubiceps coeruleus

Similar species

cigarfish
Cubiceps whiteleggii
Bigeye cigarfish
Cubiceps pauciradiatus
Cape cigarfish
Cubiceps capensis
Cigarfish
Cubiceps baxteri
Longfin cigarfish
Cubiceps gracilis
Dwarf cigarfish
Cubiceps nanus

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).
247 open-data records from 1911 to 2023.
Species data updated November 1, 2026.

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