Sphaerocoeliidae

Sphaerocoeliidae is an extinct family of calcareous sponges, the only family in the monotypic order Sphaerocoeliida. Sphaerocoeliids are one of several unrelated sponge groups described as "sphinctozoans", with a distinctive multi-chambered body structure. Sphaerocoeliids persisted from the Permian to the Cenomanian stage of the Cretaceous, a longer period of time than most other "sphinctozoans". Sphaerocoeliids make up the majority of calcareous "sphinctozoans", as well as a large portion of post-Triassic "sphinctozoan" diversity.^[1][2] "Sphinctozoans" and the similar "inozoans" were historically grouped together in the polyphyletic order Pharetronida.^[2]

Sphaerocoeliidae Temporal range: Permian–Cenomanian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Porifera
Class:	Calcarea
Order:	†Sphaerocoeliida Vacelet, 1979
Family:	†Sphaerocoeliidae Steinmann, 1882
Genera
see text.

In general form, sphaerocoeliids are cylindrical, as a chain of dome-shaped chambers stacked up on each other. Each layer is pierced by a central osculum (outflow vent), which has the form of a simple hole. Sphaerocoeliids are hypermineralized, with a skeleton of loose calcareous spicules cemented together in calcite walls.^[1][2]

Genera

• †Barroisia Munier-Chalmas, 1882 [Jurassic^[2]–Cretaceous (Aptian–Cenomanian)]
• †Sphaerocoelia Steinmann, 1882 [Permian–Cretaceous (Cenomanian)]
• †Sphinctonella Hurcewicz, 1975 [Jurassic (Oxfordian)]
• †Thalamopora Roemer, 1840 [Jurassic^[2]–Cretaceous (Cenomanian)]
• †Tremacystia Hinde, 1884 [Cretaceous (Albian–Cenomanian)]