Description: This isopod closely resembles its relative, the woodlouse. It has a long oval body that is grey to olive green in colour and divided into segments. It can reach up to 3 cm in size so it is a large isopod. It has two long antennae on its head and large black eyes. It has 7 pairs of walking legs and two uropods that project from the posterior of the animal, each of these uropods has two long projections.

Habitat: On the upper shore, in crevices, hidden under boulders or under quays or groynes.

Distribution: Found all around Britain and Ireland.

Similar Species: Unlikely to be confused with any other species. This is a large isopod with a distinctive appearance.

Key Identification Features:

• Large isopod (up to 3 cm) that resembles a woodlouse.
• Two long antennae.
• Large black eyes.
• Two long projections extending from each uropod.

Distribution Map from NBN: Ligia oceanica at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Ligia oceanica at iNaturalist World Species Observations database.

GBIF data for Ligia oceanica

WoRMS: Ligia oceanica at World Register of Marine Species. Accepted name: Ligia oceanica (Linnaeus, 1767). AphiaID: 146999.

Classification: Biota; Animalia; Arthropoda; Crustacea; Multicrustacea; Malacostraca; Eumalacostraca; Peracarida; Isopoda; Oniscidea; Diplocheta; Ligiidae; Ligia