|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.
|C. G. Barras 2007||Stem group Atelostomata with an adjunct apical disc. The disc contains no more than six complemental plates and oculars II and IValways share a direct contact. The genus retains the primitive characters of a vertically sided periproctal groove (Pl. 1, fig. 4a), oral pore pairs crowded into phyllodes (Fig. 10B) and a peristomial well (Pl. 1, fig. 4c).|