Phylum Porifera Grant, 1836 - sponges Class Hexactinellida Schmidt, 1870 - hexactinellids Subclass Amphidiscophora Schulze, 1886 Order Reticulosa Reid, 1958 Superfamily Dierespongioidea Rigby & Gutschick 1976 Family Titusvillidae Caster, 1939 see Family Titusvilliidae Caster, 1939 Genus †Sclerothamnus Marshall, 1875