Horse mussel

Modiolus modiolus

Molluscs
IUCN: Not evaluated

Usual depth5–76 m
Water temperature3–27 °C
Best monthsJuly, August, and September
How commonCommon

All species

Photo credit: (c) James St. John, some rights reserved (CC BY) · CC BY · iNaturalist

About this species

Modiolus modiolus, common name northern horsemussel, is a species of marine bivalve mollusk in the family Mytilidae.

Text from the Wikipedia article “Modiolus modiolus”, 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: 412 records
February: 399 records
March: 594 records
April: 737 records
May: 1,174 records
June: 1,289 records
July: 1,335 records
August: 2,067 records
September: 1,911 records
October: 736 records
November: 362 records
December: 213 records

Depth and water temperature

Depth

Mostly recorded at 5–76 m · Deepest record: 1,081 m

0–10 m: 1,114 records
10–20 m: 1,501 records
20–30 m: 883 records
30–40 m: 763 records
40–50 m: 397 records
50–60 m: 158 records
60–70 m: 118 records
70–80 m: 213 records
80–90 m: 172 records
90–100 m: 108 records
100–110 m: 64 records
110+ m: 147 records

Water temperature

Recorded in surface water of 3–27 °C

2–4 °C: 3 records
4–6 °C: 3 records
6–8 °C: 25 records
8–10 °C: 166 records
10–12 °C: 493 records
12–14 °C: 47 records
14–16 °C: 3 records
16–18 °C: 5 records
18–20 °C: 0 records
20–22 °C: 0 records
22–24 °C: 0 records
24–26 °C: 1 records
26–28 °C: 2 records

Photos

(c) Bren Zo, some rights reserved (CC BY), uploaded by Bren Zo · CC BY · iNaturalist
(c) Jonathan Layman, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Thor-Rune Hansen, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
(c) Cassidy Best, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist
(c) Jonathan Layman, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Vsevolod Rudyi, some rights reserved (CC BY) · CC BY · iNaturalist

Names and classification

English: Horse mussel, Horse-mussel, Northern horse mussel, Northern horsemussel, horse mussel, horse-mussel, Horse Mussel, northern horsemussel, Northern Horsemussel, Northern Horse Mussel

Names in 4 more languages

German: grose Miesmuschel, Große Miesmuschel, Pferdemuschel
French: grande moule, modiole
Japanese: エゾヒバリガイ, ムールガイ
Korean: 말홍합, 털담치

Other scientific names: Modiola gallica, Modiola gigantea, Modiola grandis, Modiola modiolus, Modiola papuana, Modiola vulgaris, Modiolus gallicus, Musculus modulus, Mytilus curtus, Mytilus curvirostratus, Mytilus curvirostrus, Mytilus modiolus, Mytilus umbilicatus

Similar species

Bearded Horse Mussel
Modiolus areolatus
Ear mussel
Modiolus auriculatus
Modiolus nipponicus
Narrow Horse Mussel
Modiolus albicosta
Philippine Horse Mussel
Modiolus philippinarum
Winged Horse Mussel
Modiolus modulaides

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).
12,524 open-data records from 1758 to 2025.
Species data updated November 4, 2026.

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