Portunus armatus
- Usual depth95.3 m
- Water temperature23–29 °C
- Best monthsOctober and November
- How commonOccasional
Photo credit: (c) Sockrosma, some rights reserved (CC BY) · CC BY · iNaturalist
About this species
Portunus armatus is a species of crustacean, a swimming crab in the family Portunidae found in Australia and eastwards to New Caledonia. Common names include blue swimmer crabs, Blue manna, Blueys, and Jennies. The species was originally considered as a geographic variation of Portunus pelagicus, however in 2010 the Portunus pelagicus species was reviewed using DNA, as well as physical characteristics including measurements and four species recognised: Portunus pelagicus, Portunus armatus, Portunus reticulatis and Portunus segnis. The range of Portunus armatus overlaps with Portunus pelagicus in the Northern Territory of Australia.
Text from the Wikipedia article “Portunus armatus”, 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: 226 records
- February: 227 records
- March: 286 records
- April: 219 records
- May: 136 records
- June: 109 records
- July: 179 records
- August: 171 records
- September: 293 records
- October: 532 records
- November: 386 records
- December: 270 records
Depth and water temperature
Depth
Mostly recorded at 95.3 m · Deepest record: 95.3 m
Water temperature
Recorded in surface water of 23–29 °C
Photos
no rights reserved · CC0 1.0 · iNaturalist 
(c) Maria Duynisveld, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Tim, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Brendan McIntyre, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Lawrence Hylton, some rights reserved (CC BY) · CC BY · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
(c) Debra Baker, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
Other scientific names: Neptunus armatus, Portunus (Portunus) armatus
Similar species
Blue swimming crabPortunus pelagicus
Blood-spotted swimming crabPortunus sanguinolentus
Gazami crabPortunus trituberculatus
- hairy swimming crab
Portunus pubescens
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).
- 425 open-data records from 1953 to 2007.
- Species data updated November 6, 2026.
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