|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|P. J. Noble and J. Maletz 2000||Large subspherical shell composed of a loose laby- rinthine mesh that forms three to four spiraliform layers. Five to seven long thin primary spines per hemisphere, average length roughly equal to shell diameter.|