Phylum Porifera Grant, 1836 - sponges Class Hexactinellida Schmidt, 1870 - hexactinellids Subclass Hexasterophora Schulze, 1886 Order Lychniscosa Schrammen, 1903 see Order Lychniscosida Schrammen, 1903 Family Dactylocalycidae Gray, 1867 Subfamily †Ophrystomatinae Schrammen, 1912 [monotypic] 1 Genus †Ophrystoma Zittel, 1877