Polybius pusillus

Polybius pusillus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Clade:	Pancrustacea
Class:	Malacostraca
Order:	Decapoda
Suborder:	Pleocyemata
Infraorder:	Brachyura
Family:	Polybiidae
Genus:	Polybius
Species:	P. pusillus
Binomial name
	Polybius pusillus; (Leach, 1815)
Synonyms
	Liocarcinus pusillus (Leach, 1816) ; Macropipus parvulus (Parisi, 1916) Macropipus pusillus (Leach, 1816) ; Portunus parvulus (Parisi, 1916) Portunus pusillus (Leach, 1816) ;

Polybius pusillus, common name dwarf swimming crab,² is a species of crab in the Portunidae family.³¹

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).³⁴ This species occurs in a wide range of colours.³ The front has three sharpened tusks, directed forward.²

Distribution

Polybius pusillus occurs from North-West Africa, to Lofoten, Norway³⁴ including the North Sea.² 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.⁵

Habitat

Specimens range intertidally up to 100 metres,⁴ dwelling on sandy to stony bottoms,³⁵ but prefer gravel or stony substrates.

References

De Grave, Sammy (6 May 2024). "Polybius pusillus (Leach, 1816)". WoRMS. World Register of Marine Species. Retrieved 13 March 2025.
"Marine Species: Liocarcinus pusillus". Skaphandrus.com. Archived from the original on 2011-07-16. Retrieved 2010-08-05.
"Liocarcinus pusillus". Seawater.no. March 20, 2009. Archived from the original on July 18, 2009. Retrieved August 5, 2010.
"Liten svømmekrabbe - Liocarcinus pusillus" (in Norwegian). Marinbi.com. Retrieved August 5, 2010.
Mario de Kluiver & Sarita Ingualso. "Liocarcinus pusillus". Macrobenthos of the North Sea - Crustacea. Marine Species Identification Portal. Retrieved August 5, 2010.

[WoRMS-1] De Grave, Sammy (6 May 2024). "Polybius pusillus (Leach, 1816)". WoRMS. World Register of Marine Species. Retrieved 13 March 2025.

[skaphandrus1-2] "Marine Species: Liocarcinus pusillus". Skaphandrus.com. Archived from the original on 2011-07-16. Retrieved 2010-08-05.

[seawater1-3] "Liocarcinus pusillus". Seawater.no. March 20, 2009. Archived from the original on July 18, 2009. Retrieved August 5, 2010.

[marinbi1-4] "Liten svømmekrabbe - Liocarcinus pusillus" (in Norwegian). Marinbi.com. Retrieved August 5, 2010.

[species-identification1-5] Mario de Kluiver & Sarita Ingualso. "Liocarcinus pusillus". Macrobenthos of the North Sea - Crustacea. Marine Species Identification Portal. Retrieved August 5, 2010.

1

2

3

4

5