This video says about itself:
Phylum Kamptozoa (Entoprocta)
30 July 2015
Also called nodding heads or goblet worms, Kamptozoans are tiny little sessile animals composed of a muscular stalk and a head with a crown of tentacles.
Translated from the Dutch Stichting ANEMOON marine biologists:
8 May 2016 – In biodiversity research for Rijkswaterstaat biologists in the North Sea have found four species new for the Netherlands of solitary entoproct animals. They are also the first species of this type of animal group found in Dutch coastal waters. Unfortunately, these Entoprocta are very small.
The four newly discovered species are Loxosomella compressa, Loxosomella harmeri, Loxosomella varians and Loxosomella phascolosomata.They are from 0.5 to 2.5 mm in size.