RESEARCH PAPER Frasnian bryozoans (Late Devonian) from the Khoshyeilagh Section, Alborz Mountains (northern Iran) Zoya Tolokonnikova • Andrej Ernst • Hamed Yarahmadzahi Received: 23 January 2011 / Accepted: 12 April 2011 / Published online: 10 May 2011 Ó Springer-Verlag 2011 Abstract A bryozoan fauna containing seven species is described from the Upper Frasnian (Upper Devonian) rocks in the Khoshyeilagh Section, Alborz Mountains (northern Iran). The studied bryozoan assemblage includes one new trepostome species, Eridotrypella alborzensis sp. nov., an additional four species identified at species level: two tre- postomes, Minussina akkayaensis Volkova, 1974 and Leptotrypella inaudita Morozova, 1961, and two rhab- domesine cryptostomes, Bigeyella mariae (Morozova, 1961) and Saffordotaxis multispinata (Morozova, 1955). Furthermore, two species are described in open nomen- clature: the trepostome Schulgina sp. and the rhabdomesine cryptostome Nicklesopora sp. The studied fauna shows a close similarity at the species level between northern Iran and the Altai-Sayan Folded Belt (Russia), south China, and Transcaucasia. Keywords Bryozoa  Frasnian  Late Devonian  Iran  Alborz Mountains Kurzfassung Es wird eine Bryozoenfauna von sieben Arten aus dem Oberfrasnium (Oberdevon) von der Lo- kalita¨t Khoshyeilagh, Alborz-Gebirge (Nordiran) besch- rieben. Die untersuchte Bryozoenassoziation entha¨lt eine neue trepostome Art, Eridotrypella alborzensis sp. nov, und vier Arten sind auf Artniveau bestimmbar: zwei tre- postome Bryozoen, Minussina akkayaensis Volkova, 1974 und Leptotrypella inaudita Morozova, 1961, sowie zwei rhabdomesine cryptostome Bryozoen, Bigeyella mariae (Morozova, 1961) und Saffordotaxis multispinata (Morozova, 1955). Des Weitern werden zwei Arten in offener Nomenklatur beschrieben: trepostome Schulgina sp. und rhabdomesine cryptostome Nicklesopora sp. Die erforschte Fauna zeigt pala¨obiogeographische Beziehungen zum Altai (Russland), Su¨dchina und dem Kaukasus auf dem Artniveau. Schlu¨ sselwo¨rter Bryozoen  Frasnium  Oberdevon  Iran  Alborz Gebirge Introduction Upper Devonian deposits are widely distributed in Iran and have been dated by conodonts and brachiopods (Mistiaen et al. 2000; Wendt et al. 2005; Ashouri 2006). These sed- iments also contain various other fossils, which can be utilised to expand the palaeontological characteristics of formations and are useful for biostratigraphy and palaeo- biogeography. Bryozoans are one of the most abundant groups in the Upper Devonian sediments of Iran. However, the current information about them is very scarce. Several bryozoan species were reported by Brice et al. (1978) from the Middle-Upper Devonian sediments of the Alborz Mountains: Fistulipora sp., Canutrypa francqana Bassler, Z. Tolokonnikova (&) Kuzbass State Pedagogical Academy, Kuznetsov Str., 6, 654041 Novokuznetsk, Russia e-mail: zalatoi@yandex.ru A. Ernst Institut fu¨r Geowissenschaften der Christian-Albrechts- Universita¨t zu Kiel, Ludewig-Meyn-Str. 10, 24118 Kiel, Germany e-mail: ae@gpi.uni-kiel.de H. Yarahmadzahi Department of Geology, Faculty of Science, Islamic Azad University of Zahedan, Zahedan, Iran e-mail: hamed.yarahmadzahi@gmail.com 123 Pala¨ontol Z (2011) 85:393–405 DOI 10.1007/s12542-011-0107-z