Iran was a persistent single tectonic unit throughout the Ordovician, located somewhere on the northern margin of Gondwana (Cocks & Torsvik 2021). Its precise rifting time from mainland Gondwana is still not defined, but the very low diversity of Ordovician brachiopod faunas in the region by comparison with contemporaneous Mediterranean Province fauna of Morocco and Bohemia suggests that Iran was situated in a high latitude location throughout the Ordovician Period (Basset et al. 1999).Ordovician marine sedimentary sequences occur in a number of widely separated structural units of Iran.Mostly but not exclusively, they crop out in the Zagros area (Southwest Iran), and in the well-known outcrops of the Alborz Range (North Iran), Tabas and Kerman regions (East-Central Iran) (Fig. 1A). Parts of the sequences contain rich fossil faunas, such as conodonts, trilobites or brachiopods, but with a small number of notable exceptions there are few studies on taxonomy, biostratigraphy and biogeography of these biotas (e.g.