Unexpected new species of deep-water Hydroidomedusae from Korsfjorden, Norway

Two new species of Hydroidomedusae, Parateclaia norvegica sp.nov. and Foersteria quadrata sp.nov., are described from specimens collected in Korsfjorden, western Norway. Neither genus has previously been observed in the North-Atlantic Ocean. The closest congenerics to the new species occur in the Mediterranean, where family Teclaiidae has been considered endemic. P. norvegica and F. quadrata were only collected at sites 500 m or deeper and are possibly deep-water benthopelagic species like their congenerics elsewhere. Sampling took place for the entire year 2003 at 2- to 4-week intervals. F. quadrata, the more numerous of the new species, was absent from the water column only during the spring months, the implications of which regarding its lifecycle are discussed. Hypotheses on speciation in the Foersteria species group and family Teclaiidae are shortly discussed.