Academic Journal
New Lower Kimmeridgian ataxioceratin ammonite from the eastern Iberian Chain, Spain: Systematic, biogeographic, and biostratigraphic relevance
| العنوان: | New Lower Kimmeridgian ataxioceratin ammonite from the eastern Iberian Chain, Spain: Systematic, biogeographic, and biostratigraphic relevance |
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| المؤلفون: | Luis Moliner, Federico Olóriz |
| المساهمون: | The Pennsylvania State University CiteSeerX Archives |
| المصدر: | http://www.app.pan.pl/archive/published/app55/app20080064.pdf. |
| سنة النشر: | 2009 |
| المجموعة: | CiteSeerX |
| الوصف: | Spain: Systematic, biogeographic, and biostratigraphic relevance. Acta Palaeontologica Polonica 55 (1): 99–110. New ammonites collected bed−by−bed from the upper part of Ataxioceras hypselocyclum Chronozone deposits in the east− ern Iberian Chain are described as Geyericeras gen. nov. The new genus includes micro − and macroconchiate Ataxio− ceratinae of small size, with moderate to loose coiling and subpolyplocoid ribs, a character crucial for its identification. Key points for the comparative identification of Geyericeras gen. nov. are: (i) microconchiate Geyericeras show morpho− logical convergence with evolute specimens of the stratigraphically older genus Schneidia [m]; (ii) contemporary Ataxioceratinae genera such as Ardescia [m, M] and Lithacosphinctes [m, M] did not develop subpolyplocoid ribbing; (iii) smoothing of sculpture combined with short primary ribs are not realized in Geyericeras gen. nov. [M] and can be therefore used to separate the new genus from Ataxioceras [M]; and (iv) smaller shells, and weaker and less dense ribbing with no parabolic structures differentiate Geyericeras gen. nov. [m, M] from Parataxioceras [m, M], as well as the type of subpolyplocoid ribs seen among microconchiate specimens of these two genera. The new species Geyericeras arago− niense sp. nov. is the index and guide fossil for identification of a biohorizon occurring below the first occurrence of the genus Crussoliceras in the eastern Iberian Chain. |
| نوع الوثيقة: | text |
| وصف الملف: | application/pdf |
| اللغة: | English |
| Relation: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.628.8345; http://www.app.pan.pl/archive/published/app55/app20080064.pdf |
| الاتاحة: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.628.8345 http://www.app.pan.pl/archive/published/app55/app20080064.pdf |
| Rights: | Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
| رقم الانضمام: | edsbas.C113D518 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |