First Record of Pojetaia Runnegari Jell, 1980 and Fordilla Barrande, 1881 from the Middle East (Taurus Mountains, Turkey) and Critical Review of Cambrian Bivalves
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Pala¨ontol Z (2009) 83:267–291 DOI 10.1007/s12542-009-0021-9 RESEARCH PAPER First record of Pojetaia runnegari Jell, 1980 and Fordilla Barrande, 1881 from the Middle East (Taurus Mountains, Turkey) and critical review of Cambrian bivalves Olaf Elicki Æ Semih Gu¨rsu Received: 25 February 2008 / Accepted: 21 March 2009 / Published online: 16 May 2009 Ó Springer-Verlag 2009 Abstract Cambrian bivalves from the Middle East are infaunal mode of life of Pojetaia and Fordilla is questioned reported here for the first time. They come from early by observations of similarly organized modern bivalves. ‘‘Middle Cambrian’’ and latest ‘‘Early Cambrian’’ lime- The palaeogeographical distribution of Pojetaia and stones of the lower C¸ al Tepe Formation at the type locality Fordilla is discussed with respect to their early ontogeny (near Seydis¸ehir, western Taurides). The majority of the and to differences in the recent state of knowledge on new findings consists of Pojetaia runnegari Jell, 1980, but shelly fossils from Cambrian carbonate successions of a few specimens of Fordilla sp. represent the first report of Perigondwana. this genus from ‘‘Middle Cambrian’’ strata. Based on a compilation of the hitherto reported, but mostly revised Keywords Cambrian Á Bivalvia Á Pelecypoda Á Cambrian bivalves, the today widely accepted taxa are small shelly fossils Á C¸ al Tepe Formation Á Turkey discussed. The genera Pojetaia Jell, 1980 and Fordilla Barrande, 1881 are critically evaluated, and three valid Zusammenfassung Erstmals fu¨r den Mittleren Osten species are included in Pojetaia: P. runnegari Jell, 1980, werden Funde kambrischer Muscheln gemeldet. Sie ent- P. sarhroensis Geyer and Streng, 1998, and—with limita- stammen Kalksteinen untermittelkambischer und ho¨chst- tions—P. ostseensis Hinz-Schallreuter, 1995. Fordilla also unterkambrischer Bereiche der tieferen C¸ al Tepe includes three species: F. troyensis Barrande, 1881, Formation an der Typuslokalita¨tC¸ al Tepe (nahe F. sibirica Krasilova, 1977, and F. germanica Elicki, 1994. Seydis¸ehir) im westlichen Taurusgebirge. Die Muscheln The Cambrian genera Tuarangia MacKinnon, 1982, werden u¨berwiegend durch die Art Pojetaia runnegari Jell, Camya Hinz-Schallreuter, 1995, and Arhouriella Geyer 1980 und untergeordnet durch Fordilla sp. repra¨sentiert. and Streng, 1998 most probably belong to the class Letztere stellt den ersten Nachweis dieser Gattung im Bivalvia. Palaeoecologically, the Cambrian bivalves of the ,,Mittelkambrium’’ u¨berhaupt dar. Ausgehend von einer Western Perigondwanan shelf seem to occur in a relatively Zusammenstellung der bisher beschriebenen und gro¨ß- small window of low-energy, subtidal, open-marine, warm- tenteils wieder revidierten kambrischen Muscheln, werden water conditions on a muddy carbonate ramp or platform die heute weitgehend akzeptierten Formen diskutiert. Ins- with reduced sedimentation rate. The frequently interpreted besondere fu¨r die Gattungen Pojetaia Jell, 1980 und For- dilla Barrande, 1881 und deren Arten werden taxonomisch verwendbare Merkmale kritisch bewertet. Danach ergeben O. Elicki (&) sich im Bestand von Pojetaia folgende gu¨ltige Arten: Geological Institute, Freiberg University, P. runnegari Jell, 1980, P. sarhroensis Geyer and Streng, Bernhard-von-Cotta street 2, 09599 Freiberg, Germany e-mail: [email protected] 1998 und—mit Einschra¨nkung—P. ostseensis Hinz- Schallreuter, 1995. In der Gattung Fordilla werden die S. Gu¨rsu Arten F. troyensis Barrande, 1881, F. sibirica Krasilova, Mineralogy-Petrography Division, General Directorate 1977 und F. germanica Elicki, 1994 gefu¨hrt. Als of Mineral Research and Exploration (MTA), Ankara, Turkey ho¨chstwahrscheinlich den Bivalvia zuzuordnende, weitere e-mail: [email protected] kambrische Gattungen werden Tuarangia MacKinnon, 123 268 O. Elicki, S. Gu¨rsu 1982, Camya Hinz-Schallreuter, 1995 und Arhouriella http://www.stratigraphy.org). The consensus on the subdi- Geyer and Streng, 1998 angesehen. Pala¨oo¨kologisch vision of the Cambrian system is into four series consisting scheinen die kambrischen Muscheln des Perigondwana- of ten stages. At present, lower boundaries of two series and Schelfs innerhalb eines relativ schmalen Fensters aufzut- four stages are defined. Following this new chronostrati- reten, welches niedrigenergetische, subtidale, offenmarine graphic subdivision, the traditional ‘‘Lower Cambrian/Early Warmwasserverha¨ltnisse auf einer feinko¨rnigen Karbonat- Cambrian’’ approximately corresponds to the two lower rampe oder -plattform mit geringer Sedimentationsrate series (Terreneuvean and unnamed ‘‘series 2’’), the tradi- repra¨sentiert. Die zumeist interpretierte, infaunale Lebens- tional ‘‘Middle Cambrian’’ corresponds approximately to weise von Pojetaia und Fordilla erscheint im Vergleich unnamed ‘‘series 3,’’ and the traditional ‘‘Upper Cambrian/ mit a¨hnlich gebauten rezenten Muscheln als nicht Late Cambrian’’ corresponds approximately to the Furon- hinreichend belegt. Die pala¨ogeographische Verbreitung gian. Because of the still unnamed Cambrian series and von Pojetaia und Fordilla wird mit Blick auf deren fru¨he stages, and for better reading, in this paper we use ‘‘Early Ontogenese und hinsichtlich des Bearbeitungsstandes von Cambrian’’, ‘‘Middle Cambrian’’, and ‘‘Late Cambrian’’ Schalenfossilien kambrischer Karbonatfolgen Perigond- (written in quotation marks) as informal terms. wanas diskutiert. The figured specimens are housed in the Geological Institute of Freiberg University under collection number Schlu¨sselwo¨rter Kambrium Á Bivalvia Á Pelecypoda Á FG 600. small shelly Fossilien Á C¸ al Tepe Formation Á Tu¨rkei Geological setting Introduction The Taurus Mountains represent the western segment of Palaeontological data from the Cambrian period of the the Taurides, located in the southern part of the Anatolian eastern Mediterranean are restricted to a few regions of the Peninsula. The Taurides are a Gondwana-derived fragment Turkish and the Arabian plates, but mainly work on trilo- and represent an Alpine range that includes numerous bites and brachiopods has been reported. Non-trilobitic and tectono-stratigraphic units that piled up during the closure non-brachiopod Cambrian fossils are sporadically men- of the Neotethyan ocean in the Eastern Mediterranean in tioned from Jordan, Israel, and Turkey (overviews in the Late Cretaceous to Lutetian times (S¸ engo¨r and Yılmaz Rushton and Powell 1998; Sarmiento et al. 2001; Shinaq 1981;Go¨ncu¨og˘lu 1997;Go¨ncu¨og˘lu et al. 2004). A detailed and Elicki 2007). The two last-mentioned references are classification of the tectono-stratigraphic units within the the only papers on investigations of small shelly fossils, Taurides is suggested by O¨ zgu¨l(1976), who subdivided the although many recent investigations in the western Medi- Geyik Dag˘ı, Bozkır, Bolkar, Aladag˘, Alanya, and Antalya terranean and in Central Europe have shown that Cambrian units, respectively. Major Alpine tectonic units of the small shelly fossils have a great potential for reconstruction Tauride–Anatolide Belt are shown in Fig. 1. of palaeo-environments and palaeogeography (Elicki 1994, The Neoproterozoic basement and overlying early Pal- 1998, 2005, 2007; Ferna´ndez-Remolar 2001; Elicki and aeozoic succession are best exposed in the Geyik Dag˘ı unit Wotte 2003; Elicki and Pillola 2004; Gubanov et al. 2004; of the Central and Western Taurides. A generalized cor- Wotte 2006). relation of formations in the Geyik Dag˘ı unit in the Central This paper presents the first results of a project on and Eastern Taurides is given in Fig. 2. Basement rocks are Cambrian small shelly faunas from Turkey and is focused disconformably overlain by ‘‘Early Cambrian’’ siliciclas- on bivalves. The project will contribute to the reconstruc- tics of the Go¨g˘ebakan Fm. and Hu¨dai Fm., which are fol- tion of depositional conditions and of the palaeogeography lowed by carbonate rocks of the ‘‘Early’’ to ‘‘Middle of the western Gondwana shelf during the Cambrian period Cambrian’’ C¸ al Tepe Fm., and subsequently by siliciclas- and to the clarification of trans-regional relations of the tics of the ‘‘Late Cambrian’’ to Ordovician Seydis¸ehir Fm. Mediterranean faunas to those farther East. in the Central Taurides (detailed in Gu¨rsu and Go¨ncu¨og˘lu Although the global chronostratigraphic subdivision of 2001;Gu¨rsu et al. 2004). the Cambrian system by the International Commission on The type section of the C¸ al Tepe Fm. (Fig. 3), from Stratigraphy (ICS) has been introduced, most workers still where the material reported here comes, is located at the use the traditional terms Lower, Middle, and Upper C¸ al Tepe hill a few kilometers north of Seydis¸ehir, at the Cambrian. The new stratigraphic subdivision (Babcock and northern side of the Taurus Mountains, southern Turkey. Peng 2007) is still in progress, and not yet all of the The stratotype was defined by Dean and Monod (1970). Cambrian series and stages have been named and defined by According to Dean and Monod (1970, 1995) and Dean GSSP (for the actual state of affairs, see the ICP website at (1980, 2005), the formation is divided into four members. 123 First record of Pojetaia runnegari Jell, 1980 and Fordilla Barrande, 1881 269 Fig. 1 Alpine tectonic units of the Tauride-Anatolite Belt of Turkey (adapted from Go¨ncu¨og˘lu et al. 1997) These are in ascending order: (1) Dolomite Mbr. (more problematic because of rare preservation of the first two than 50 m), (2) Black Limestone Mbr. (24 m), (3) Light characters. Nevertheless, if they