A sea slater (Idotea pelagica)
|Researched by||Dr Harvey Tyler-Walters||Refereed by||Admin|
|Other common names||-||Synonyms||-|
A dorso-ventrally flattened crustacean with an elongated rounded oblong shaped body. Body mostly dark purple to brown with white diamond-shaped patches or stripes down the midline and white markings along the edges of the body. Females tend to be darker than males. Males range in length from 4-11 mm and females from 7-10 mm. The distinctive head bears two dorso-lateral eyes, a pair of short antennules, and a pair of antennae. Most of body is taken up by a thorax composed on seven sections (somites). The body ends in a short abdomen (two somites) and a distinct tail-piece (the pleotelson). The antennule extend to the third segment of the antenna. The antenna is robust with a short flagellum that is densley covered with hairs in males. The pleotelson in adults is characteristic, with straight or slightly convex sides, a rounded end and only an indistinct middle tooth or process.
Recorded distribution in Britain and IrelandProbably distributed all around the coasts of Britain and Ireland but poorly represented in surveys.
Global distributionRecorded form Norway to the French coast but not entering low salinity waters of the inner Baltic.
HabitatFound on wave exposed rocky shores amongst barnacles, mussels and stunted fucoids.
- Dorso-ventrally flattened and oblong, oval body.
- Abdomen (pleon) consists of two complete somites and one partial suture.
- Antennule just or equal in length to the third section of the antenna.
- Antennal flagellum shorter than its peduncle, less than one sixth of the body length, and densely covered in hairs in males.
- Pleotelson sides straight or slightly convex, rounded with only an indistinct, blunt tooth.
- Tops of the legs bear broad coxal plates that widen posteriorly.
- Legs are very robust and bear a relatively larger claw than other Idotea.
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Environmental Records Information Centre North East, 2018. ERIC NE Combined dataset to 2017. Occurrence dataset: http://www.ericnortheast.org.ukl accessed via NBNAtlas.org on 2018-09-38
NBN (National Biodiversity Network) Atlas. Available from: https://www.nbnatlas.org.
OBIS (Ocean Biodiversity Information System), 2023. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2023-10-04
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Last Updated: 23/05/2005