Idotea wosnesenskii have hooked claws that allow them to attach strongly to seaweeds.
Attachment of Idotea to brown seaweeds was stronger than to rock, Ulva lactuca (green algae) or Pyropia sp. (red algae).
Differences in attachment strength are relevant to velocities commonly experienced and may limit isopod distribution.
Attachment strength was strongly correlated with material properties of the seaweed hosts.