Rounded swimming crab

Lupocyclus rotundatus

Crustaceans
IUCN: Not evaluated

Usual depth17–105 m
Water temperature22–29 °C
Best monthsSeptember, October, and November
How commonOccasional

All species

Where and when

Where it has been recorded

Worldwide

Loading the map

Best months

Worldwide (open data)

January: 23 records
February: 5 records
March: 3 records
April: 16 records
May: 14 records
June: 7 records
July: 2 records
August: 4 records
September: 60 records
October: 49 records
November: 39 records
December: 18 records

Depth and water temperature

Depth

Mostly recorded at 17–105 m · Deepest record: 104.8 m

10–20 m: 2 records
20–30 m: 0 records
30–40 m: 0 records
40–50 m: 0 records
50–60 m: 0 records
60–70 m: 0 records
70–80 m: 1 records
80–90 m: 1 records
90–100 m: 0 records
100–110 m: 4 records

Water temperature

Recorded in surface water of 22–29 °C

22–24 °C: 13 records
24–26 °C: 89 records
26–28 °C: 128 records
28–30 °C: 7 records

Names and classification

English: Rounded swimming crab, rounded swimming crab

Similar species

Lupocyclus philippinensis
Five-toothed Swimming Crab
Lupocyclus quinquedentatus
Lupocyclus inaequalis
Lupocyclus strigosus
Lupocyclus tugelae
Blue swimming crab
Portunus pelagicus

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.
Conservation status as published by GBIF (IUCN Red List).
304 open-data records from 1909 to 2007.
Species data updated November 4, 2026.

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