Coffin Ray

Hypnos monopterygius

Sharks and rays
IUCN: Least concern

Usual depth17–79 m
Water temperature13–27 °C
Best monthsFebruary, May, and November
How commonOccasional

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

About this species

Hypnos monopterygius, also known as the coffin ray or Australian numbfish, is a species of electric ray endemic to Australia, where it is common in inshore waters shallower than 80 m (260 ft). It is the sole member of its genus Hypnos, and family Hypnidae. This small species typically reaches 40 cm (16 in) in length. Greatly enlarged pectoral fins and an extremely short tail, coupled with diminutive dorsal and caudal fins all concentrated towards the rear, give the coffin ray a distinctive pear-like shape. It is a varying shade of brown in colour above, and has tiny eyes and a large, highly distensible mouth.

Text from the Wikipedia article “Coffin ray”, 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: 102 records
February: 186 records
March: 147 records
April: 136 records
May: 153 records
June: 81 records
July: 103 records
August: 99 records
September: 91 records
October: 81 records
November: 152 records
December: 96 records

Depth and water temperature

Depth

Mostly recorded at 17–79 m · Deepest record: 440 m

0–10 m: 1 records
10–20 m: 127 records
20–30 m: 126 records
30–40 m: 51 records
40–50 m: 19 records
50–60 m: 114 records
60–70 m: 50 records
70–80 m: 130 records
80–90 m: 33 records
90–100 m: 6 records
100–110 m: 4 records
110+ m: 15 records

Water temperature

Recorded in surface water of 13–27 °C

12–14 °C: 2 records
14–16 °C: 1 records
16–18 °C: 15 records
18–20 °C: 17 records
20–22 °C: 249 records
22–24 °C: 245 records
24–26 °C: 2 records
26–28 °C: 2 records

Photos

(c) Josh Nitschke, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Sofia Zvolanek, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist
(c) Tim, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Belinda Forbes, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Niko Ioannidis, some rights reserved (CC BY) · CC BY · iNaturalist

Names and classification

English: Coffin Ray, Crampfish, Numbie

Other scientific names: Hypnarce monopterygia, Hypnos monopterygium, Hypnos subnigrum, Lophius monopterygius

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).
881 open-data records from 1898 to 2007.
Species data updated November 3, 2026.

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