A collection of hexactinellids (Porifera) from the deep South Atlantic and North Pacific: new genus, new species and new records.

This article describes or redescribes four hexactinellid sponges, namely Poliopogon amadou, Euplectella sanctipauli sp. nov., Bolosoma perezi sp. nov. and Advhena magnifica gen. et sp. nov. P. amadou, E. sanctipauli sp. nov. and B. perezi sp. nov. represent new findings for the South Atlantic deep-sea fauna, including the first record of Bolosoma for this ocean. Advhena magnifica gen. et sp. nov., on the other hand, was collected by NOAA oceanographic expeditions in the North Pacific (Pigafetta Guyot).