Sponges comprise the second largest group of animals preserved in the Middle Cambrian Burgess Shale Formation of British Columbia. A total of 48 sponge species belonging to 26 genera are now known from the Burgess Shale Formation and the coeval Stephen Formation. This is the most diverse sponge fauna known from the Cambrian.
In the Burgess Shale Formation, most of the sponges are distributed in six distinct communities found in different localities in Yoho National Park at different stratigraphic levels.
Biostratigraphically, the oldest, the Collins Quarry community on Mount Stephen, occurs in the Glossopleura Zone, Polypleuraspis Subzone. The other five communities are in the overlying Bathyuriscus-Elrathina Zone, with the three oldest in the Pagetia bootes Subzone, and the two youngest in the Pagetia walcotti Subzone. The remaining sponges are scattered sparsely throughout the Burgess Shale Formation over a distance of 60 km in Yoho and Kootenay National Parks, sponges also occur in the seventh, and youngest, community in the Stephen Formation.
The sponges described here come from over 3000 specimens collected in 18 field seasons between 1975 and 2000 by Royal Ontario Museum parties. They include the new demosponge genera Hamptoniella, Ulospongiella and Hapalospongia, with the latter two included in the new family Ulospongiellidae; the new hexactinellid genus Protoprisma; and the new heteractinid genus Eiffelospongia. New species include Eiffelospongia hirsuta gen. nov. et n. sp., Falospongia ramosa sp. nov., Hamptonia elongata sp. nov., Hamptoniella foliata gen. nov et sp. nov., Hamptoniella hirsuta gen. nov. et sp. nov., Hapalospongia flexuosa gen. nov. et sp. nov., Hazelia lobata sp. nov.. Leptomitella incepta sp. nov., Leptomitus undulatus sp. nov., Protoprisma annulata gen. nov. et sp. nov.. Ulospongiella ancyla gen. nov. et sp. nov., Vauxia irregulara sp. nov. and Wapkia elongata sp. nov. The demosponge genus, Leptomitella, is new to the Burgess Shale Formation, as are the hexactinellid, Diagoniella cyathiformis (Dawson, 1889) and the demosponges Choia hindei (Dawson, 1896), and Fieldospongia bellilineata (Walcott, 1920). The Utah hexactinellid, Hintzespongia bilamina Rigby and Gutschick, 1976, is reported from the Stephen Formation. The heteractinid, Petaloptyon danei Raymond, 1931, is reassigned from the gorgonian octocorals. Sentinelia draco Walcott, 1920, is deemed an unrecognizable taxon, whereas Vauxia ampliata Rigby, 1986, is shown not to be a sponge.