Kurzfassung
Die ungewöhnliche diplograptide GraptolithenartUndulograptus dicellograptoides n. sp. aus derUndulograptus dentatus Zone des späten Arenigs des westlichen Neufundlands wird nach chemisch aus Schiefern isoliertem Material beschrieben. Die Art besitzt zwei reklinate Äste und erinnert in der Rhabdosomform an die stratigraphisch jüngere GattungDicellograptus. Ein mehrfacher, unabhängiger Ursprung der Entwicklung dicellograptider bis dicranograptider Rhabdosomformen in den Diplograptina wird diskutiert.
Abstract
The unusual diplograptidUndulograptus dicellograptoides n. sp. from the late ArenigUndulograptus dentatus Zone of western Newfoundland is described from isolated material. The species bears two reclined stipes and resembles a species of the stratigraphically younger genusDicellograptus. The dicellograptid to dicranograptid rhabdosome form appeared several times independently in the Diplograptina.
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Maletz, J. Undulograptus dicellograptoides n. sp., an abnormal diplograptid from the Late Arenig of western Newfoundland, Canada. Paläontol Z 72, 111–116 (1998). https://doi.org/10.1007/BF02987820
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DOI: https://doi.org/10.1007/BF02987820