Seven-arm octopus

Haliphron atlanticus

Cephalopods
IUCN: Least concern

Usual depth0–1,323 m
Water temperature9–29 °C
Best monthsJune, July, and August
How commonRare

About this species

The seven-arm octopus, also known as the blob octopus or sometimes called septopus, is one of the two largest known species of octopus; the largest specimen ever discovered had an estimated total length of 3.5 m (11 ft) and mass of 75 kg (165 lb). The only other similarly large extant species is the giant Pacific octopus, Enteroctopus dofleini.

Text from the Wikipedia article “Seven-arm octopus”, 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: 19 records
March: 17 records
April: 17 records
May: 32 records
June: 56 records
July: 60 records
August: 51 records
September: 31 records
October: 13 records
November: 5 records
December: 4 records

Depth and water temperature

Depth

Mostly recorded at 0–1,323 m · Deepest record: 2,841 m

0–10 m: 161 records
10–20 m: 1 records
20–30 m: 0 records
30–40 m: 5 records
40–50 m: 1 records
50–60 m: 0 records
60–70 m: 0 records
70–80 m: 1 records
80–90 m: 0 records
90–100 m: 0 records
100–110 m: 5 records
110+ m: 91 records

Water temperature

Recorded in surface water of 9–29 °C

8–10 °C: 4 records
10–12 °C: 9 records
12–14 °C: 17 records
14–16 °C: 15 records
16–18 °C: 42 records
18–20 °C: 208 records
20–22 °C: 15 records
22–24 °C: 10 records
24–26 °C: 13 records
26–28 °C: 12 records
28–30 °C: 8 records

Names and classification

English: Seven-arm octopus, Haliphron, Seven-armed Octopus, Seven-arm Octopus

Names in 3 more languages

Japanese: カンテンダコ
Thai: ปลาหมึกสายเจ็ดหนวด
Simplified Chinese: Yì-Fū-Xiāo, 異夫蛸

Other scientific names: Alloposus hardyi, Alloposus mollis, Alloposus pacificus, Bolitaena microcotyla, Haliphron hardyi, Haliphron pacificus, Heptapus danai

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).
456 open-data records from 1880 to 2024.
Species data updated November 3, 2026.

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