Blood clam

Tegillarca granosa

Molluscs
IUCN: Not evaluated

Usual depth0–287 m
Water temperature14–30 °C
Best monthsAugust, October, and December
How commonOccasional

About this species

Tegillarca granosa is a species of ark clam commonly known as the blood cockle or blood clam due to the red haemoglobin liquid inside the soft tissues. It is found throughout the Indo-Pacific region from the eastern coast of South Africa northwards and eastwards to Southeast Asia, Australia, Polynesia, and up to northern Japan. It lives mainly in the intertidal zone at one to two metres water depth, burrowed down into sand or mud. Adult size is about 5 to 6 cm long and 4 to 5 cm wide.

Text from the Wikipedia article “Tegillarca granosa”, 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: 2 records
February: 4 records
March: 6 records
April: 12 records
May: 10 records
June: 7 records
July: 7 records
August: 22 records
September: 11 records
October: 28 records
November: 7 records
December: 18 records

Depth and water temperature

Depth

Mostly recorded at 0–287 m · Deepest record: 287 m

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

Water temperature

Recorded in surface water of 14–30 °C

14–16 °C: 1 records
16–18 °C: 0 records
18–20 °C: 2 records
20–22 °C: 7 records
22–24 °C: 1 records
24–26 °C: 15 records
26–28 °C: 35 records
28–30 °C: 135 records

Names and classification

English: Blood clam, Blood cockle, Granular ark, blood clam, blood cockle, granular ark, Granular Mud Ark

Names in 4 more languages

German: Genarbte Arche, Genarbte Archenmuschel, Westpazifische Archenmuschel
Japanese: ハイガイ
Korean: 꼬막
Simplified Chinese: 血蚶

Other scientific names: Anadara (Tegillarca) granosa, Anadara bisenensis, Anadara granosa, Anadara thackwayi, Anomalocardia pulchella, Arca (Anadara) granosa, Arca aculeata, Arca corbicula, Arca corbula, Arca granosa, Arca nodulosa, Arca obessa

Similar species

Divaricated Ark
Acar plicata
Antique ark
Anadara antiquata
Indo-Pacific Ark
Arca navicularis
Burnt-almond ark
Barbatia amygdalumtostum
Kagoshima Blood Cockle
Anadara kagoshimensis
Sydney Cockle
Anadara trapezia

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).
622 open-data records from 1758 to 2024.

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