Crown-of-thorns

About this species

The crown-of-thorns starfish is a large starfish that preys upon hard coral polyps. The crown-of-thorns starfish, frequently abbreviated to COTS, receives its name from venomous, thornlike spines that cover its upper surface, resembling the biblical crown of thorns. It is one of the largest starfish in the world.

Text from the Wikipedia article “Crown-of-thorns starfish”, 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: 183 records
February: 84 records
March: 74 records
April: 51 records
May: 164 records
June: 102 records
July: 83 records
August: 67 records
September: 672 records
October: 219 records
November: 82 records
December: 88 records

Depth and water temperature

Depth

Mostly recorded at 4–18 m · Deepest record: 287 m

0–10 m: 285 records
10–20 m: 917 records
20–30 m: 5 records
30–40 m: 0 records
40–50 m: 0 records
50–60 m: 0 records
60–70 m: 3 records
70–80 m: 0 records
80–90 m: 0 records
90–100 m: 0 records
100–110 m: 0 records
110+ m: 2 records

Water temperature

Recorded in surface water of 21–30 °C

20–22 °C: 14 records
22–24 °C: 6 records
24–26 °C: 103 records
26–28 °C: 54 records
28–30 °C: 156 records

Photos

(c) luluchouette, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Jakkarin Burananit, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Donald Davesne, some rights reserved (CC BY) · CC BY · iNaturalist
(c) nbasargin, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Darren Obbard, some rights reserved (CC BY) · CC BY · iNaturalist
(c) CaracalShan, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Peggy Newman, some rights reserved (CC BY) · CC BY · iNaturalist

Names and classification

English: Crown-of-thorns, crown-of-thorns, Crown of thorns starfish, Crown-of-thorns starfish, Indian crown-of-thorns, Long-spined Crown-of-Thorns, Long-spined Crown-of-Thorns Sea Star, purple crown-of-thorns

Names in 6 more languages

German: Dornenkronenseestern
Spanish: Corona de espinas, Estrella de mar corona de espinas
French: Acanthaster du Pacifique, acanthaster pourpre, Acanthaster pourpre, Couronne du Christ, Couronne d’épines, Coussin de belle-mère, Couronne d'épines
Japanese: オニヒトデ
Thai: ดาวมงกุฎหนาม
Simplified Chinese: 棘冠海星

Other scientific names: Acanthaster echinites, Acanthaster echinus, Acanthaster ellisi, Acanthaster pseudoplanci, Acanthaster solaris, Asterias echinites, Asterias echinus, Asterias planci, Asterias solaris, Echinaster ellisi, Echinaster solaris, Echinities solaris, Stellonia echinites

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).
2,147 open-data records from 1743 to 2024.
Species data updated October 26, 2026.