Striatocycloceras undulostriatum (Hall, 1847)

Taxon description

Kröger & Isakar, 2006

Diagnosis. Slightly curved, slightly compressed Striatocycloceras with very low apical angle of approximately 2°.Adult dorsoventral diameter approximately more than 30 mm, with four to six annulations at a distance that equates the corresponding shell diameter in adult. Annulations slightly oblique, irregularly spaced, with faint lobe at the sidein opposition of the siphuncle. Distinct growth lines, 10––12 per cycle of annulations, one or two cycles of annulations per chamber. Suture lines run slightly oblique in relation to annulations forming a slight sinus at the side opposite to the siphuncle. Siphuncle subcentral. Short, orthochoanitic septal neck.

Synonymy list
1847     Orthoceras undulostriatum — Hall , pp. 202, fig. 43:7
1850     Orthoceratites undulostriatum — dOrbigny , pp. 3
1858     Orthoceratites undulostriatum — Salter , pp. 375, fig. Pl. 13:25,26
1915     Orthoceratites undulostriatum — Bassler , pp. 918
1932     Cycloceras undulostriatum — Foerste , pp. 87, fig. Fig: 12:3-4
2006     Striatocycloceras undulostriatum (Hall, 1847) — Kröger & Isakar , pp. 150, fig. 7L, 8E, 10A
2012     Striatocycloceras undulostriatum (Hall, 1847) — Kröger , pp. 25
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. 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
References based on distribution