• Norwegian: eremittkrepshydroide

Characteristics:

Hydroid stage: The snail fur forms a 3 mm horny mat with 1-2 mm spines. The polyps may grow to a height of 13 mm. There are four types of polyps:

  • The club shaped hydranths have two circles of tentacles, with eight tentacles in each.
  • Female and male gonozooids are shorter and have fewer tentacles. The gonozooids spawn planula (free-swimming) larvae. These detect detect moving shells and attach themselves to them.
  • The dactylozooids are long threadlike individuals.

Medusa stage: No information.

Habitat:

This tiny hydroid may occasionally be found on rocky substrate, but is more common on shells inhabited by hermit crabs or on the shell of the common whelk.

Distribution:

This hydroid is well known along the European coasts, from the Mediterranean to the Arctic.