Cycloachelous granulatus

Crustaceans
IUCN: Not evaluated

Usual depth4–40 m
Water temperature20–30 °C
Best monthsApril, September, and November
How commonRare

All species

Photo credit: (c) Gabriel, some rights reserved (CC BY) · CC BY · iNaturalist

Where and when

Where it has been recorded

Worldwide

Loading the map

Best months

Worldwide (open data)

January: 7 records
February: 10 records
March: 11 records
April: 40 records
May: 11 records
June: 11 records
July: 8 records
August: 3 records
September: 34 records
October: 31 records
November: 39 records
December: 16 records

Depth and water temperature

Depth

Mostly recorded at 4–40 m · Deepest record: 40 m

0–10 m: 1 records
10–20 m: 0 records
20–30 m: 0 records
30–40 m: 0 records
40–50 m: 1 records

Water temperature

Recorded in surface water of 20–30 °C

20–22 °C: 2 records
22–24 °C: 15 records
24–26 °C: 73 records
26–28 °C: 120 records
28–30 °C: 16 records

Photos

(c) Daniel Eisenhauer, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist
(c) Gabriel, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Cricket Raspet, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Dominik Maximilián Ramík, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Saryu Mae 前朝琉, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist

Names and classification

Names in 2 more languages

Japanese: サメハダヒメガザミ
Simplified Chinese: 顆粒圓水神蟹, 顆粒梭子蟹

Other scientific names: Achelous granulatus, Amphitrite speciosa, Lupea granulata, Neptunus (Achelous) granulatus, Neptunus granulatus, Portunus (Achelous) granulatus, Portunus (Portunus) granulatus

Similar species

Cycloachelous suborbicularis
Cycloachelous orbitosinus
Blue swimming crab
Portunus pelagicus
Asian paddle crab
Charybdis (Charybdis) japonica
Portunus armatus
Blood-spotted swimming crab
Portunus sanguinolentus

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).
292 open-data records from 1834 to 2023.
Species data updated November 1, 2026.

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