Granular isopod (Idotea granulosa)
|Researched by||Sonia Rowley||Refereed by||Admin|
|Other common names||-||Synonyms||-|
Idotea granulosa has an elongated body that is oval in shape, sharply narrowing posteriorly and dorsoventrally flattened. The antennae are less than one-fifth of the overall body length. Males are 5-20 mm in length, where females are 6-13 mm in length. It is uniformally brown, red or green with occasional white longitudal markings along its back. In adults pleotelson initially narrows quite sharply having concave lateral sides & forming a distinct median blunt point.
Recorded distribution in Britain and IrelandRecorded throughout Britain & Ireland, but absent on most of the east coast of England. This species may be under recorded.
HabitatThis is an species found feeding on algae, on open, but not overly-exposed coasts.
- Elongated oval shaped body, sharply narrowing and dorsoventrally flattened.
- Body length is males 5-20 mm and 6-13 mm in females.
- Uniformally brown, red or green in colour.
- Occasional white markings along its back.
- Antennae one-fifth of body length.
Idotea granulosa colour varies depending on the nature of the algae inhabited. Larger specimens are found on the brown algae Ascophyllum nodosum and Fucus spp. Smaller specimens are found on green algae Cladophora spp. and Polysiphonia spp.
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Kent Wildlife Trust, 2018. Biological survey of the intertidal chalk reefs between Folkestone Warren and Kingsdown, Kent 2009-2011. Occurrence dataset: https://www.kentwildlifetrust.org.uk/ accessed via NBNAtlas.org on 2018-10-01.
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Manx Biological Recording Partnership, 2018. Isle of Man historical wildlife records 1990 to 1994. Occurrence dataset: https://doi.org/10.15468/aru16v accessed via GBIF.org on 2018-10-01.
Manx Biological Recording Partnership, 2018. Isle of Man historical wildlife records 1995 to 1999. Occurrence dataset: https://doi.org/10.15468/lo2tge accessed via GBIF.org on 2018-10-01.
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Norfolk Biodiversity Information Service, 2017. NBIS Records to December 2016. Occurrence dataset: https://doi.org/10.15468/jca5lo accessed via GBIF.org on 2018-10-01.
OBIS (Ocean Biodiversity Information System), 2023. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2023-12-10
Outer Hebrides Biological Recording, 2018. Invertebrates (except insects), Outer Hebrides. Occurrence dataset: https://doi.org/10.15468/hpavud accessed via GBIF.org on 2018-10-01.
South East Wales Biodiversity Records Centre, 2018. SEWBReC Myriapods, Isopods, and allied species (South East Wales). Occurrence dataset: https://doi.org/10.15468/rvxsqs accessed via GBIF.org on 2018-10-02.
Yorkshire Wildlife Trust, 2018. Yorkshire Wildlife Trust Shoresearch. Occurrence dataset: https://doi.org/10.15468/1nw3ch accessed via GBIF.org on 2018-10-02.
This review can be cited as:
Last Updated: 24/11/2005