The pharciceratid ammonoids from the Roteisenstein Formation of Dillenburg (Cephalopoda, Ammonoidea) Author Korn, Dieter 286CA4F3-7EBC-4AEF-A66A-B2508D001367 Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstrasse 43, 10115 Berlin, Germany. dieter.korn@mfn.berlin Author Bockwinkel, Jürgen F7FE7EEA-B678-4FEE-879C-8C429F66BF3A Dechant-Fein-Strasse 22, 51375 Leverkusen, Germany. jbockwinkel@t-online.de text European Journal of Taxonomy 2021 2021-09-23 771 1 79 http://dx.doi.org/10.5852/ejt.2021.771.1503 journal article 4091 10.5852/ejt.2021.771.1503 d4ff05b4-fdac-44e8-8c2e-0733a93169a0 2118-9773 5536097 9FAB6919-E4AC-44A6-89AB-2E236F55FDB5 Subfamily Pharciceratinae Hyatt, 1900 Diagnosis Pharciceratidae with open umbilicus in all growth stages; umbilical width ratio decreasing in the adult stage. Suture line with four to six umbilical lobes. Included genera Pharciceras Hyatt, 1884 ; Allopharciceras Bockwinkel, Becker & Aboussalam, 2017 ; Extropharciceras Bockwinkel, Becker& Ebbighausen, 2009 ; Lunupharciceras Korn in Korn & Klug, 2002 ; Oxypharciceras Bockwinkel, Becker & Aboussalam, 2017 ; Sphaeropharciceras Bogoslovsky, 1955 (probably synonym of Pharciceras ); Transpharciceras Bockwinkel, Becker & Ebbighausen, 2013 ; Evopharciceras gen. nov. Remarks Bogoslovsky (1955) introduced the genus Sphaeropharciceras ; the species S. sandbergerorum , which was newly named by him at the same time, was determined as the type species. This species was based on an illustration by Sandberger & Sandberger (1850 –1856: pl. 9 fig. 2), in which a small ( 13 mm conch diameter), almost globular specimen is shown. The specimen was then figured and briefly discussed by House (in House & Ziegler 1977 : pl. 5 figs 24–26). House concluded that the distorted specimen has to be included in Pharciceras tridens . Unfortunately, this specimen is now considered lost; therefore, it cannot be verified whether it is indeed to be considered a synonym of P. tridens . Owing to the small size, however, it should hardly be possible to formulate a satisfactory species diagnosis.