Family Liroceratidae Miller & Youngquist, 1949 Diagnosis Family of the superfamily Liroceratoidea with a usually pachyconic or globular, subinvolute to subevolute conch. Whorl profile in the adult stage usually more or less strongly depressed; flanks and venter form a continuous arch in the early species, the venter can be flattened or concave in advanced species. Umbilical margin rounded; umbilical wall usually convex. Ornament usually consisting of fine growth lines; spiral lines occur in some genera. Septum simple in shape, concavely domed; suture line very simple, almost straight across flanks and venter or with small lobes and saddles (from Korn 2025). Included genera Solenoceras Hyatt, 1884 [homonym of Solenoceras Conrad, 1860; objective synonym of Coelogasteroceras]; Coelogasteroceras Hyatt, 1893 (Carboniferous to Permian); Coloceras Hyatt, 1893 [homonym of Coloceras Taschenberg, 1882; synonym of Liroceras Teichert, 1940]; Stearoceras Hyatt, 1893 (Carboniferous to Permian); Peripetoceras Hyatt, 1894 (Carboniferous to Permian); Potoceras Hyatt, 1894 (Carboniferous); Nannoceras Hyatt, 1894 [nomen nullum; synonym of Peripetoceras]; Conradiceras Cossmann, 1900 [objective synonym of Coelogasteroceras]; Liroceras Teichert, 1940 (Carboniferous to Permian); Condraoceras Miller, Lane & Unklesbay, 1947 (Carboniferous to Permian); Periptoceras Chao, 1954 [nomen nullum; synonym of Peripetoceras]; Hemiliroceras Ruzhencev & Shimansky, 1954 (Carboniferous to Permian); Bistrialites Turner, 1954 (Carboniferous); Pseudophacoceras Turner, 1966 (Carboniferous); Neobistrialites Tucker, Mapes & Aronoff, 1978 (Carboniferous); Jianoceras Ma, 1997 (Permian); Nemdoceras Barskov & Shilovsky, 2014 (Permian); Paraliroceras Barskov & Shilovsky, 2014 (Permian); Tatianautilus Barskov & Shilovsky, 2014 (Permian); Leniceras Leonova & Shchedukhin, 2020 (Permian); Shikhanonautilus Leonova & Shchedukhin, 2020 (Permian); Thyoceras Leonova & Shchedukhin, 2020 (Permian); Celeroliroceras gen. nov. (Permian); Perunautilus Crick & Sobolev, 1994 (Triassic); Tomponautilus Sobolev, 1989 (Triassic). Remarks A detailed discussion of the Liroceratidae has been given by Korn (2025).

Published as part of Korn, Dieter & Ghaderi, Abbas, 2025, Late Permian nautiloids from Julfa (NW Iran), pp. 1-113 in European Journal of Taxonomy 1018 on pages 81-82, DOI: 10.5852/ejt.2025.1018.3069, http://zenodo.org/record/17234867