Tainoceratina
Introduction ''For a further discussion of this group as in use today, see the superfamily Tainocerataceae''The '''Tainoceratina''' is a suborder within the Nautilida (Kümmel 1964) created by Shimanskiy  on the assumption that the initial, or embryonic, whorl was the critical phylogenetic indicator, which resulted in combining otherwise unrelated and separating obviously related forms. The Tainoceratina rearranges the precedented Tainocerataceae while excluding the ancestral Rutoceratidae.Three families, the Tainoceratidae, Tetragonoceratidae, and Rhiphaeoceratidae are in common with the Tainocerataeae, but with somewhat different meaning and content. Six additional families used in the Tainoceratina, the Actubonautilidae, Encoiloceratidae, Gzheloceratidae, Mosquoceratidae,  Pleuronautilidae, and Temnocheilidae  result from mixing genera from this family and that and redefining established families. None of these latter six are in common usage today.The Encoiloceratidae, Gzheloceratidae, Mosquoceratidae, and  Pleuronautilidae are found in the Tainoceratidae; the Temnocheilidae in the Koninckioceratidae, and the Actubonautilidae  in the Rhiphaeoceratidae. According to Kümmel (1964) the Pleuronautilidae might be considered a subfamily within the Tainoceratidae, which would include, ''Encoiloceras'', the only genus in the Encoiloceratidae.The Tainoceratina differs conceptually from the Tainocerataceae in that the Tetragonoceratidae is the ancestral family, derived from the Rutocerida rather than being an offshoot from the Rutoceratidae and that the various families included within are combined in unique superfamilies.
References * Kümmel, B, 1964.Nautiloidea-Nautilida; Treatise on Invertebrate Paleontology, Part K ; Geological Society of America and University of Kansas press; Teichert & Moore,(eds) *  Paleobiology Database ;  see families in text.