Cephalopoda

Orthoceratidae McCoy, 1844

Taxon description

Kröger & Isakar, 2006

Emended diagnosis. Orthocones with slender, central orsubcentral, tubular or moderately expanded siphuncle. Septalnecks suborthochoanitic or orthochoanitic, respectively. Shellsmooth or annulated, with more or less well developed longi-tudinal and transverse ribs, ridges or combination of these.Ornamentation usually more well-developed in shell parts oflater growth stages. Bowl-shaped apical shell small, straight,without cicatrix, without initial constriction, smooth or orna-mented with transversal and longitudinal elements, but with-out annulations. Endosiphuncular and cameral deposits occuronly in most apical chambers of quasi-mature specimens

Selection of related publications
Kröger, B. & Aubrechtová, M. 2018. Cephalopods from reef limestone of the Vasalemma Formation, northern Estonia (latest Sandbian, Upper Ordovician) and the establishment of a local warm-water fauna. Journal of Systematic Palaeontology 16, 10, 799-839. DOI:10.1080/14772019.2017.1347212
Kröger, B. 2013. The cephalopods of the Boda Limestone, Late Ordovician, of Dalarna, Sweden. European Journal of Taxonomy 41, 1-110. DOI:10.5852/ejt.2013.41
Kröger, B., Ebbestad, J. O., Högström, A. E. S. & Frisk, A. M. 2011. Mass concentration of Hirnantian cephalopods from the Siljan District, Sweden; palaeoecology and palaeobiogeographic relationships. Fossil Record 14, 1, 35-53. DOI:10.1002/mmng.201000014
Kröger, B. 2007. Concentrations of juvenile and small adult cephalopods in the Hirnantian cherts (Late Ordovician) of Porkuni, Estonia. Acta Palaeontologica Polonica 52, 3, 591-608.
Kröger, B. & Isakar, M. 2006. Revision of annulated orthoceridan cephalopods of the Baltoscandic Ordovician. Fossil Record 9, 1, 137-163. DOI:10.1002/mmng.200600005
Kröger, B. 2004. Revision of Middle Ordovician orthoceratacean nautiloids from Baltoscandia. Acta Palaeontologica Polonica 49, 1, 57-74.
Mutvei, H. 2002. Connecting ring structure and its significance for classification of the orthoceratid cephalopods. Acta Palaeontologica Polonica 47, 1, 157-168.
Rõõmusoks, A. 1970. Stratigraphy of the Viruan Series (Middle Ordovician) in Northern Estonia, I.
Balashov, Z. G. 1956. On the systematic position and stratigraphic meaning of the species Orthoceras. Yearbook of All-Union Paleontological Society XV, 223-247.
Stumbur, H. A. 1956. On the nautiloids of Kohila Subseries (Upper Ordovician of East Baltic). Tartu Riikliku Ülikooli Toimetised 42, 176-185.
Stumbur, H. 1955. Eesti NSV ülem-ordoviitsiumi nautiloididest. Diplomitöö; 16 fototahvlit, materjali nimekiri Stumburi tööde kaustas, pp. 1-159.
Alichova, T. N., Balashova, E. A. & Balashov, Z. G. 1954. Field atlas of characteristic Ordovician and Silurian faunas of southern Lithuania.
Teichert, C. 1930. Die Cephalopoden-Fauna der Lyckholm-Stufe des Ostbaltikums. Paläontologische Zeitschrift 12, 3/4, 264-312. DOI:10.1007/BF03044452
Öpik, A. 1927. Die Inseln Odensholm und Rogö. Ein Beitrag zur Geologia von NW Estland. Tartu Ülikooli Geoloogia Instituudi Toimetused 9, 70.
Schlotheim, E. F. von 1820. Die Petrefactenkunde auf ihrem jetzingen Standpuncte durch die Beschreibung seiner Sammlung versteinerter und fossiler Überreste des Thier-und Pfanzenreichs der Vorwelt erläuteri.