Shells unilocular and multichambered (pseudomultichambered as an exception), predominant shell types - uniserial, high-trochospiral (in a special polymorphinoid spire, absent in any other taxa), planospiral (nearly exceptionally involute), typical trochospiral type is absent completely; chambers often subcircular, triangular, V-shaped, palmate, inner additional skeletal chamber septa only in one fossil taxa (Collaniellidae), outer shell sculpture well developed in secretious forms, but outer additional skeletal plates are absent, integrative systems poorly developed (stolons and tunnels absent, inner apertural systems occurred rarely, canal system marked only in Delosinida, purely studied); wall monofontinal, agglutinated or microgranular in the lower representatives (Hormosinana), in the higher ones (Nodosariana) - hyaline-radial, with regular pseudopores having cylindrical pseudopore canaliculi but without additional sieve-plates (according to the literature basal sieve-plate present),growth interrupted, process of forming of the new chambers has not been studied ; aperture terminal even in the coiled forms, singular or multiple, simple or radial, slit-like, asymmetrically-fissured, hooded, all the apertural types may be with entosolenian tube, (non analogues to the apertural structures of Rotaliata), (radial, asymmetrically fissured and hooded aperture, as well as entosolenian tube are unique and are found only in this class), additional apertures absent completely; data on nuclear apparatus and gamete structure absent; mostly free-living, bottom forms, one parasitic species is described. Ordovician - Holocene.