Author(s): Janssen, N. M. M. & Főzy, I.
Title: Neocomian belemnites from the Bersek-hegy (Gerecse Mountains, Hungary), part II: Barremian
Year: 2005
Volume: 23
Pages: 59-86.
Abstract: The belemnite faunas from the Lower and lower Upper Barremian sedimentary rocks of the Bersek-hegy (Gerecse Mts, Hungary) are described within the framework of a precise ammonite stratigraphy and compared to faunas from other regions. A new genus (Conohibolites) is introduced for Belemnites gr. platyurus Duval-Jouve, 1841. In the previous part, Adiakritobelus was introduced for the Valanginian - lowermost Hauterivian part of the "Mesobibolitef auct. This genus includes the species Belemnites minaret Raspail, 1829 (former genotype of Mesohibolites Stolley, 1919). However, the generic name "Mesohibolites" auct. pl., generally used for a group of late Barremian to early Aptian belemnites, is proposed as a nomen conservandum, with Mesohibolites uhligi (Shvetsov, 1913) as a new genotype (proposal forwarded; pending validation of the ICZN). A zonation based on the distribution of belemnites is proposed for the Lower to lower Upper Barremian. At least two different belemnite associations
characterize the sediments under investigation. One characteristic for the lowermost Barremian, with D. gagrica Shvetsov, 1913, D. silesiaca Uhrig, 1902 (Duvaliidae), Hibolithes gr. subfusiformis (Raspail, 1829), and Hibolithes jaculiformis Shvetsov, 1913 (Mesohibolitidae). These belemnites occur in the Hugii, Nicklesi, and probably the Pulchella Zone of the Mediterranean Tethys. Around the boundary between the Pulchella and the Compressissima Zone these belemnites are replaced by Duvalia gr. grasiana (DUVAL-JOUVE, 1841) (Duvaliidae) and new genera of Mesohibolitidae, i.e. Curtohibolites, Conohibolites and "Mesohibolites". This new fauna association characterizes the sediments, which are herein called "mid"-Barremian, being approximately equivalent of the top of the Lower Barremian and the base of the Upper Barremian. Not until the Upper Barremian FeraudianusGiraudi Zones, a complete different association of belemnites (Mesohibolites sensu stricto) is found. These belemnites make a diverse and characteristic faunal-component of the uppermost Barremian and Lower Aptian (Bedoulian).Keywords: Barremian, Tethys, belemnites, ammonites, Conohibolites n gen, Curtohibolites, Mesohibolites
Journal: Fragmenta Palaeontologica HungaricaJournal abbreviation: Fragm. Palaeont. Hung.ISSN: 1586-930XPublisher: Hungarian Natural History Museum, BudapestEditor(s): Szabó, J. & Matskási, I.