Hydrozoer: Hydractinia echinata.

The hydroid colonies of this species are known as snail fur or eremittkrepshydroider because they often grow on snail shells inhabited by hermit crabs, giving the shell a furry appearance. These names are unfortunately a little misleading, since Hydractinia echinata is not the only hydractiniid that grows on hermit crab shells, and neither is it restricted to this substrate. A good sign to recognize this common shallow water species is the presence of large spines with ‘serrated’ (spiky) edges.

Hydractinia echinata Fleming, 1828
Creative Commons Attribution | Lara Beckmann | Joan J. Soto-Àngel | Aino Hosia | Luis Martell | Universitetsmuseet i Bergen, Universitetet i Bergen
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