Common Rock Crab
Hemigrapsus sexdentatus
- Usual depth0–11 m
- Water temperature12–18 °C
- Best monthsJanuary, April, and December
- How commonOccasional
Photo credit: (c) Jon Sullivan, some rights reserved (CC BY) · CC BY · iNaturalist
About this species
Hemigrapsus sexdentatus, also called the “common rock crab” or “common shore crab,” is a marine crab indigenous to the southern shores of New Zealand. This crab is a member of the Varunidae family in the order Decapoda.
Text from the Wikipedia article “Hemigrapsus sexdentatus”, 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: 60 records
- February: 50 records
- March: 33 records
- April: 85 records
- May: 36 records
- June: 43 records
- July: 35 records
- August: 27 records
- September: 44 records
- October: 55 records
- November: 43 records
- December: 62 records
Depth and water temperature
Depth
Mostly recorded at 0–11 m · Deepest record: 40 m
Water temperature
Recorded in surface water of 12–18 °C
Photos
(c) Jon Sullivan, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Uwe Schneehagen, some rights reserved (CC BY-SA), uploaded by Uwe Schneehagen · CC BY-SA · iNaturalist (c) Steve Kerr, some rights reserved (CC BY), uploaded by Steve Kerr · CC BY · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
(c) wild_wind, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) John Barkla, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) wild_wind, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Common Rock Crab, Common Shore Crab, New Zealand Shore Crab
Other scientific names: Brachynotus edwardsii, Cyclograpsus sexdentatus, Hemigrapsus edwardsi, Hemigrapsus edwardsii, Heterograpsus sexdentatus
Similar species
Asian shore crabHemigrapsus sanguineus
Estuarine crabHemigrapsus crenulatus
Common Japanese intertidal crabHemigrapsus penicillatus
Asian brush crabHemigrapsus takanoi
Tunneling Mud CrabAustrohelice crassa
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).
- 161 open-data records from 1926 to 2019.
- Species data updated November 3, 2026.
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