Revision of Middle Devonian conodont biostratigraphy in the Negheleh section, Central Iran

Fifteen conodont species and subspecies from the Negheleh section, Soh area, north of Esfahan represent early Eifelian to middle Givetian time interval. Five biozones: costatus to australis, kockelianus, ensensis to hemiansatus, timorensis and rhenanus to ansatusare recognized. The present study suggests the Eifelian age for the base of Bahram Formation in the Sanandaj-Sirjan and the western part of Central Iran Microplate. The oldest known occurrence of thelodont turiinid species, Neoturinia hutkensis is reported from the early Eifelian strata of the Negheleh section. New age range from the late Eifelian to late Frasnian is proposed for Icriodus excavatus Weddige.Keywords: Middle Devonian, Eifelian, Givetian, conodonts, biostratigraphy.