In the "Eastern Pontides" (NE Turkey), the intense volcanic activity accompanying carbonate-siliceous sedimentation during the Late Cretaceous period ensured the occurrence of thick volcano-sedimentary sequences. Seventy-one radiolarian species belonging to 26 genera were identified from five stratigraphic sections of the Upper Cretaceous sequences between Trabzon and Giresun areas in NE Turkey. These species were obtained from the lower Turonian-lower Coniacian strata of the Cesmeler Formation, the Coniacian-lower Santonian strata of the Elmah Dere Formation and the upper Santonian strata of the Caglayan Formation. Coniacian-Campanian fauna, consisting of planktonic foraminifera Hedbergella, Marginotruncana, Globotruncana, Whiteinella and biserial heterohelicids as well as radiolarians, was recovered from the red pelagic limestones of the Elmah Dere Formation known as marker horizon. (C) 2017 Elsevier Ireland Ltd Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Published by Elsevier B.V. All rights reserved.