Hexactinellids comprise diverse types of sponges viewed as solitary ones. They used to constitute the basis of sponge communities in the Middle-Late Jurassic and Middle Cretaceous of the European region. The morphological diversity of unitary forms is determined by the skeletal structure with combination of a goblet, a shaft, a false shaft and a system of rhizoids. The goblet wall is peculiar for the highest morphological flexibility, which contributes to substantial habitus changes of the skeleton original morphotypes.
