Blue-spotted Urchin

Astropyga radiata

Other invertebrates
IUCN: Not evaluated

Usual depth4–107 m
Water temperature18–29 °C
Best monthsMarch, April, and November
How commonOccasional

Photo credit: (c) FredD, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist

About this species

Astropyga radiata, the red urchin, fire urchin, false fire urchin or blue-spotted urchin, is a species of sea urchin in the family Diadematidae. It is a large species with long spines and is found in the tropical Indo-Pacific region. It was first described in 1778 by the German naturalist Nathaniel Gottfried Leske.

Text from the Wikipedia article “Astropyga radiata”, 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: 56 records
February: 35 records
March: 84 records
April: 80 records
May: 61 records
June: 49 records
July: 46 records
August: 67 records
September: 65 records
October: 49 records
November: 69 records
December: 52 records

Depth and water temperature

Depth

Mostly recorded at 4–107 m · Deepest record: 1,773 m

0–10 m: 5 records
10–20 m: 5 records
20–30 m: 1 records
30–40 m: 1 records
40–50 m: 4 records
50–60 m: 7 records
60–70 m: 0 records
70–80 m: 0 records
80–90 m: 0 records
90–100 m: 1 records
100–110 m: 2 records
110+ m: 2 records

Water temperature

Recorded in surface water of 18–29 °C

18–20 °C: 1 records
20–22 °C: 0 records
22–24 °C: 1 records
24–26 °C: 6 records
26–28 °C: 3 records
28–30 °C: 40 records

Photos

(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Bernard DUPONT, some rights reserved (CC BY) · CC BY · iNaturalist
(c) portioid, some rights reserved (CC BY) · CC BY · iNaturalist
(c) desertnaturalist, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Kai Squires, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist

Names and classification

English: Blue-spotted Urchin, Radiant Sea Urchin

Names in 4 more languages

German: Roter Diademseeigel
French: Oursin rouge
Japanese: アカオニガゼ
Simplified Chinese: 星肛海膽

Other scientific names: Asteropyga radiata, Astropyga elastica, Astropyga freudenbergi, Astropyga major, Astropyga mossambica, Cidaris radiata, Cidarites radiata, Diadema radiatum, Echinus radiatus, Echionanthus major

Similar species

Savigny's Longspine Sea Urchin
Diadema savignyi
Diadema setosum
Banded sea urchin
Echinothrix calamaris
Blue-black urchin
Echinothrix diadema
Chaetodiadema granulatum
Eremopyga debilis

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).
129 open-data records from 1778 to 2016.
Species data updated October 26, 2026.

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