Fibrocoelia tubantiensis Van Kempen, 1978
Discussion — Van Kempen (1978) established Fibrocoelia tubantiensis based on a single specimen from Early Pleistocene fluvial deposits in a sand- and gravel-pit near Kloosterhaar, the Netherlands. This type specimen was housed in the palaeontological collections of the Geological Institute of the Amsterdam University (registration number PA 8690). After the closing of the Institute, the specimen was temporarily in Van Kempen’s private collection. After his death in 2002, his collection moved to the (then) Nationaal Natuurhistorisch Museum, Leiden. However, the present author, acting as solicitor, noticed that a small number of registered sponges were missing. Some time ago, Mrs. Van Kempen re-discovered a box, containing among others the actual holotype. The specimen is now reposited in the collections of the Netherlands Centre for Biodiversity – Naturalis, Leiden, registered as RGM 550 579.
An unnumbered specimen of Fibrocoelia tubantiensis from Pliocene fluvial deposits on the Island of Sylt, northwestern Germany, appeared to be in the same box. It had been donated by the late Ulrich von Hacht of Hamburg, apparently after the publication of Fibrocoelia in 1978, because the latter specimen was not described by Van Kempen. The scarcity of material warrants a repository in the same collections as where the holotype is housed, registered as RGM 550 580.