The Clapper Hydroid is a pelagic species that is primarily polar in distribution and is found in the Arctic, Atlantic, Mediterranean and Pacific Oceans; it is also found in subtropical and temperate areas (
Sealifebase 2011) "Exhibits both asexual and sexual reproduction by budding during hydroid stage and release of gametes in medusae stage; Max length : 1.8 cm H male/unsexed (
SeaLifeBase 2011).