Greater blue-ringed octopus
Hapalochlaena lunulata
- Usual depth1–8 m
- Water temperature18–30 °C
- Best monthsJanuary, April, and May
- How commonRare
Photo credit: (c) desertnaturalist, some rights reserved (CC BY) · CC BY · iNaturalist
About this species
The greater blue-ringed octopus is one of four species of extremely venomous blue-ringed octopuses belonging to the family Octopodidae. This particular species of blue-ringed octopus is known as one of the most toxic marine animals in the world.
Text from the Wikipedia article “Greater blue-ringed 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: 31 records
- February: 17 records
- March: 22 records
- April: 32 records
- May: 28 records
- June: 20 records
- July: 16 records
- August: 18 records
- September: 10 records
- October: 15 records
- November: 15 records
- December: 22 records
Depth and water temperature
Depth
Mostly recorded at 1–8 m · Deepest record: 7.5 m
Water temperature
Recorded in surface water of 18–30 °C
Photos
(c) Kai Squires, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Nadezhda Bortnikova, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Alicia Christman, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Gregor Bailar, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Gregor Bailar, some rights reserved (CC BY) · CC BY · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist
Names and classification
- English
- Greater blue-ringed octopus, Blue-ringed Octopus, greater blue-ringed octopus
Names in 5 more languages
- German
- Großer Blaugeringelter Krake
- Spanish
- Pulpo de Anillos Azules
- French
- Poulpe à anneaux bleus, poulpe aux anneaux bleus
- Japanese
- オオマルモンダコ
- Simplified Chinese
- 大藍環章魚
Other scientific names: Octopus lunulatus
Similar species
Big blue octopusOctopus cyanea
Algae OctopusAbdopus aculeatus
Old woman octopusCistopus indicus
Mimic octopusThaumoctopus mimicus
WonderpusWunderpus photogenicus
- Mosaic Drop-arm Octopus
Abdopus abaculus
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).
- 38 open-data records from 1948 to 2000.
- Species data updated October 26, 2026.
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