cf. Halichondria sp.
According to Finks et al. (2004), Halichondria is known from the Oligocene to Recent, while Schrammen (1910) describes Halichondria vosmaeri as a new species from the Upper Cretaceous of Nettlingen, but not from Misburg or Höver.
The specimen shown here matches the descriptions for Halichondria species. The skeleton is composed of felt-like masses of amphioxes or similar monaxonic needles which make up the walls between a cavernous tube system. There is a depression on the apex of the sponge which appears to be an oscule.