Savigny's Longspine Sea Urchin

Diadema savignyi

Other invertebrates
IUCN: Not evaluated

Usual depth3–17 m
Water temperature18–29 °C
Best monthsApril, June, and September
How commonOccasional

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

About this species

Diadema savignyi is a species of long-spined sea urchin belonging to the family Diadematidae. Common names include long-spined sea urchin, black longspine urchin and the banded diadem. It is native to the east coast of Africa, the Red Sea, the Indian Ocean and western Pacific Ocean. It was first described in 1829 by the French naturalist Jean Victoire Audouin. The specific epithet honours the French zoologist Marie Jules César Savigny who described many new marine species from the Mediterranean Sea and Red Sea. The type locality is Mauritius.

Text from the Wikipedia article “Diadema savignyi”, licensed CC BY-SA 4.0. Read the article

Where and when

Where it has been recorded

Worldwide

Loading the map

Best months

Worldwide (open data)

January: 156 records
February: 155 records
March: 150 records
April: 176 records
May: 152 records
June: 160 records
July: 132 records
August: 132 records
September: 200 records
October: 156 records
November: 138 records
December: 125 records

Depth and water temperature

Depth

Mostly recorded at 3–17 m · Deepest record: 2,320 m

0–10 m: 76 records
10–20 m: 154 records
20–30 m: 0 records
30–40 m: 0 records
40–50 m: 0 records
50–60 m: 8 records
60–70 m: 0 records
70–80 m: 0 records
80–90 m: 0 records
90–100 m: 0 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: 15 records
22–24 °C: 56 records
24–26 °C: 21 records
26–28 °C: 59 records
28–30 °C: 113 records

Photos

(c) Robin White, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Cricket Raspet, some rights reserved (CC BY) · CC BY · iNaturalist
(c) natomik, some rights reserved (CC BY) · CC BY · iNaturalist
(c) natomik, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Thomas Irvine, some rights reserved (CC BY) · CC BY · iNaturalist
(c) cello caruso-turiello, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist

Names and classification

English: Savigny's Longspine Sea Urchin

Names in 3 more languages

French: Oursin diadème, Oursin-diadème de Savigny
Japanese: アオスジガンガゼ
Simplified Chinese: 沙氏冠海膽, 藍環冠海膽

Other scientific names: Centrechinus savignyi, Centrostephanus savignyi, Cidarites savignyi, Diadema globulosum

Similar species

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).
746 open-data records from 1809 to 2023.
Species data updated October 26, 2026.

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