Roundbelly cowfish

Lactoria diaphana

Fish
IUCN: Least concern

Usual depth25–114 m
Water temperature13–29 °C
Best monthsAugust, September, and October
How commonOccasional

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

About this species

Lactoria diaphana, the roundbelly cowfish, diaphonous cowfish, many-spined cowfish, spiny cowfish or transparent cowfish, is a species of marine ray-finned fish belonging to the family Ostraciidae, the boxfishes. This fish is found in the southeastern Atlantic Ocean and the Indo-Pacific.

Text from the Wikipedia article “Lactoria diaphana”, 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: 49 records
February: 48 records
March: 43 records
April: 48 records
May: 36 records
June: 56 records
July: 47 records
August: 176 records
September: 172 records
October: 197 records
November: 60 records
December: 30 records

Depth and water temperature

Depth

Mostly recorded at 25–114 m · Deepest record: 1,148 m

0–10 m: 6 records
10–20 m: 26 records
20–30 m: 60 records
30–40 m: 89 records
40–50 m: 53 records
50–60 m: 58 records
60–70 m: 49 records
70–80 m: 54 records
80–90 m: 47 records
90–100 m: 25 records
100–110 m: 41 records
110+ m: 66 records

Water temperature

Recorded in surface water of 13–29 °C

12–14 °C: 1 records
14–16 °C: 2 records
16–18 °C: 3 records
18–20 °C: 12 records
20–22 °C: 33 records
22–24 °C: 31 records
24–26 °C: 63 records
26–28 °C: 390 records
28–30 °C: 10 records

Photos

(c) Henry de Lange, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Nicola Crockford, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Nicola Crockford, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Yoshihiro Tokue, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Pauline Walsh Jacobson, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Thomas Mesaglio, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist

Names and classification

English: Roundbelly cowfish, Spiny boxfish, Many-spined Cowfish, roundbelly cowfish, spiny boxfish, Spiny Boxfish, Spiny Cowfish, Transparent Boxfish

Names in 2 more languages

Spanish: cofre espinoso
Japanese: Umisuzume, ウミスズメ

Other scientific names: Lactoria diaphanus, Lactoria diaphinus, Lactoria schlemmeri, Ostracion brevicornis, Ostracion diaphanum, Ostracion diaphanus

Similar species

Longhorn cowfish
Lactoria cornuta
Thornback cowfish
Lactoria fornasini
Spotted boxfish
Ostracion meleagris
Scrawled cowfish
Acanthostracion quadricornis
Black-spotted Boxfish
Ostracion cubicum
Shortnose boxfish
Ostracion nasus

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).
976 open-data records from 1929 to 2024.
Species data updated November 3, 2026.

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