Casmaria erinaceus

Molluscs
IUCN: Not evaluated

Usual depth3–56 m
Water temperature9–30 °C
Best monthsJuly, August, and October
How commonRare

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

About this species

Casmaria erinaceus, common name : the common bonnet, is a species of large sea snail, a marine gastropod mollusk in the family Cassidae, the helmet snails and bonnet snails.

Text from the Wikipedia article “Casmaria erinaceus”, 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: 8 records
February: 13 records
March: 11 records
April: 10 records
May: 14 records
June: 11 records
July: 18 records
August: 17 records
September: 8 records
October: 15 records
November: 5 records
December: 13 records

Depth and water temperature

Depth

Mostly recorded at 3–56 m · Deepest record: 56 m

0–10 m: 5 records
10–20 m: 0 records
20–30 m: 0 records
30–40 m: 0 records
40–50 m: 2 records
50–60 m: 1 records

Water temperature

Recorded in surface water of 9–30 °C

8–10 °C: 1 records
10–12 °C: 0 records
12–14 °C: 0 records
14–16 °C: 0 records
16–18 °C: 0 records
18–20 °C: 0 records
20–22 °C: 1 records
22–24 °C: 7 records
24–26 °C: 31 records
26–28 °C: 56 records
28–30 °C: 85 records

Photos

(c) Takaaki Hattori, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Takaaki Hattori, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist

Names and classification

Names in 2 more languages

Japanese: ヒナヅルガイ
Simplified Chinese: 小鬘螺

Other scientific names: Buccinum erinaceus, Buccinum meles, Buccinum vibex, Casmaria erinacea, Casmaria vibexmexicana, Cassis (Casmaria) vibexmexicana, Cassis denticulata, Cassis glabra, Cassis vibex, Cassis vibexmexicana, Phalium edentulum, Phalium erinaceum, Phalium vibex

Similar species

Atlantic casmaria
Casmaria ponderosa
Giant helmet
Cassis cornuta

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).
403 open-data records from 1758 to 2022.
Species data updated October 26, 2026.

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