Genus

Orbisiana Sokolov, 1976

Taxon description

Kolesnikov et al., 2018a

Original description (translated from Russian): Integral aggregates of large (up to 2–3 mm) cells forming elongated and irregular clusters; cell walls are often pyritised (sokolov, 1976, p. 138).

Emended diagnosis: Compact elongate grape-like clusters and irregular aggregates of globular chambers (0.25–2 mm in diameter). Chamber size tends to be uniform within each cluster or aggregate, but varies among individuals