Polybius pusillus
species of crustacean
Polybius pusillus, common name dwarf swimming crab, is a species of crab in the Portunidae family.
Description
Polybius pusillus is a small, colourful species with a broad, suboval carapace having a maximum width of 25 mm (1.0 in). However, most specimens are usually less than 20 mm (0.8 in). This species occurs in a wide range of colours. The front has three sharpened tusks, directed forward.
Distribution
Polybius pusillus occurs from North-West Africa, to Lofoten, Norway including the North Sea. It is found around the shores of: England, in such places as Northumberland, Yorkshire, The Wash, Thames, the eastern English Channel, Isle of Wight, Portland, Plymouth, the Scilly Isles, the Bristol Channel, Liverpool Bay; Scotland - Shetland, Orkney, Firth of Forth, Argyll and Clyde, The Minch; Ireland, occurring in and around Dublin, Belfast, County Mayo, Galway Bay, Fastnet Rock, County Cork; and elsewhere in the British Isles including the Channel Islands, Anglesey and the Isle of Man.
Habitat
Specimens range intertidally up to 100 metres, dwelling on sandy to stony bottoms, but prefer gravel or stony substrates.
The public source identifies “Polybius pusillus” as species of crustacean. This brief keeps that definition visible, then builds a research path around Polybius, pusillus and species.
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Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Mar 23, 2025. The linked authority identifier is Q3022018. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Polybius pusillus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.