De Glimmende franjeschildvoet Chaetoderma nitidulum (Lovén, 1844) in de Nederlandse Noordzee

The Glistenworm Chaetoderma nitidulum (Lovén, 1844) is a mollusc with a worm-shaped, silvery and shiny appearance due to the scales and calcareous spines that cover the body. It belongs to the class of the Caudofoveata and the family of the Chaetodermatidae. Despite the fact that the species is widely distributed over the Boreal and Arctic areas and in European waters it is not often found. One explanation may be that the species is not easily recognized as a mollusc. But it could also be that the animal prefers deeper water. However, in deeper water C. nitidulum is scarcer than other Caudofoveata. Therefore, it is more likely that C. nitidulum is indeed less common than other species within this class. C. nitidulum is the only species of the Caudofoveata known to live in the Dutch part of the North Sea; it was found on Oyster Grounds and Dogger Bank in 1986-1991. Thereafter, there were no additional reports of the species from the Dutch part of the North Sea. However, during two benthic surveys performed in 2015, seven specimens of C. nitidulum were found at four different locations on the Oystergrounds, and three specimens were found at one location on Cleaver Bank.