|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.
|W. Hantzschel 1975||Ovoid or rounded masses of shell fragments and sand-size microfossils cemented by calcite; 3 to 7 cm long; upper surface mostly flat or slightly concave, smooth or somewhat granular; lower surface convex, covered by groups of short more or less parallel ridges inclined to long axis of structure.|