Introducing some echinoderms from the Tirgan Formation, Kopeh-Dagh Basin, NE of Iran

A stratigraphic section from the Tirgan Formation was selected in Arkan village nearby Bojnourd city in order to study echinoderm fauna systematically. Many specimens of echinoderms, especially toxasteridae which is associated with brachiopods were collected and studied systematically in this paper. Microscopie slides were also prepared and studied. All slides contain benthic foraminifers and calcareous algae as well as gastropod and coral fragments. Based upon diagnostic micro and macro fossils, a Barremian-Aptian age is assigned to the Tirgan Formation which suggests Urgonien facies type indicating shallow water of open marine environment.