Awakened heart sea urchin

Holanthus expergitus

Other invertebrates
IUCN: Not evaluated

Usual depth533–2,898 m
Water temperature3–29 °C
Best monthsApril
How commonRare

All species

Where and when

Where it has been recorded

Worldwide

Loading the map

Best months

Worldwide (open data)

January: 0 records
February: 5 records
March: 22 records
April: 37 records
May: 0 records
June: 6 records
July: 5 records
August: 10 records
September: 15 records
October: 14 records
November: 17 records
December: 5 records

Depth and water temperature

Depth

Mostly recorded at 533–2,898 m · Deepest record: 4,146 m

320–330 m: 1 records
330–340 m: 1 records
340–350 m: 0 records
350–360 m: 0 records
360–370 m: 0 records
370–380 m: 0 records
380–390 m: 0 records
390–400 m: 0 records
400–410 m: 0 records
410–420 m: 0 records
420–430 m: 1 records
430+ m: 149 records

Water temperature

Recorded in surface water of 3–29 °C

2–4 °C: 1 records
4–6 °C: 0 records
6–8 °C: 0 records
8–10 °C: 4 records
10–12 °C: 26 records
12–14 °C: 47 records
14–16 °C: 35 records
16–18 °C: 13 records
18–20 °C: 8 records
20–22 °C: 6 records
22–24 °C: 7 records
24–26 °C: 6 records
26–28 °C: 11 records
28–30 °C: 6 records

Names and classification

English: Awakened heart sea urchin, awakened heart sea urchin

Names in 1 more languages

French: oursin éveillé

Other scientific names: Hemiaster (Integraster) expergitus, Hemiaster (Integraster) zonatus, Hemiaster expergitus, Hemiaster mentzi, Hemiaster mentzii, Hemiaster zonatus

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.
Conservation status as published by GBIF (IUCN Red List).
189 open-data records from 1885 to 2017.
Species data updated November 3, 2026.

Log what you see on your next dive

The free DiveHive diver app keeps your logbook with every sighting and shows what lives at the site you dive next.

Join the waitlist