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A New Early Cambrian Lobopod-Bearing Animal (Murero, Spain) and the Problem of the Ecdysozoan Early Diversification

  • José Antonio Gámez VintanedEmail author
  • Eladio Liñán
  • Andrey Yu. Zhuravlev

Abstract

A new xenusian, Mureropodia apae gen. and sp. nov., is found in the lower Cambrian of the Murero Lagerstätte in the Cadenas Ibéricas, NE Spain. In Mureropodia, the lobopod length/body width ratio reveals that this animal hardly was able to walk on the bottom surface. Possibly, it could use the limbs for anchoring the body to the substrate. A well-developed dermomuscular sac of circular and longitudinal muscular systems as well as probably retractile proboscis fit such an interpretation. The ground plan of the Xenusia includes a vermiform body; a proboscis or mouth cone; paired lobopods with claws; a cuticle displaying a repeated anatomical patterning; a straight digestive tract with terminal mouth and anus. Morphologically heterogeneous xenusians, which crawled with their lobopods along the bottom, might give rise to four morphofunctional lineages – to cephalorhynch worms by adaptation for burrowing with retractable proboscis; to tardigrades by adaptation for interstitial habitat; to euarthropods by adaptation to walking on joint appendages; and to anomalocaridids by adaptation to swimming with lateral flaps.

Keywords

Lower Cambrian Muscle Bundle Stem Group Mouth Cone Terminal Claw 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

We thank sincerely the Association pour l’Étude de l’Évolution Biologique, and Prof. Pierre Pontarotti (Université de Provence, Marseilles), organizers of the 14th Evolutionary Biology Meeting at Marseilles (France), for the invitation to participate in the meeting and to publish this paper. This is a contribution to the projects: Consolíder CGL2006–12975/BTE (“MURERO”; Ministerio de Educación y Ciencia-FEDER–EU, Spain), Grupo Consolidado E–17 (“Patrimonio y Museo Paleontológico”; Gobierno de Aragón), ACI2009–1307 (Ministerio de ciercia e Innovación, Spain), and IGCP 587 (“Of Identity, Facies and Time, the Ediacaran (Vendian) Puzzle”). JAGV received financial support from the Ministerio de Ciencia e Innovación of Spain (“Juan de la Cierva” contract, ref. JCI-2009-05319). AZ benefited from the grants MI042/2006, Departamento de Ciencia, Tecnología y Universidad (Gobierno de Aragón) and CB 3/08 Programa Europa XXI de Estancias de Investigación (CAI–CONAI + D) 2008. Ms I. Pérez Urresti (MEC-European Social Fund-Universidad de Zaragoza) and Mrs Anastasia Besedina assisted with some of the drafting, and we are grateful for their contribution. Mr Ignacio Tacchini Ciudad (Instituto de Carboquímica, CSIC, Zaragoza) and Ms Ana Cristina Gallego Benedicto (Servicios de Apoyo a la Investigación, Universidad de Zaragoza) took the SEM micrographs.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • José Antonio Gámez Vintaned
    • 1
    Email author
  • Eladio Liñán
    • 2
  • Andrey Yu. Zhuravlev
    • 2
    • 3
  1. 1.Área de Paleontología, Depto. de Geología, Fac. de BiológicasUniversitat de ValènciaBurjassotSpain
  2. 2.Área y Museo de Paleontología, Depto. de Ciencias de la Tierra, Fac. de CienciasUniversidad de ZaragozaZaragozaSpain
  3. 3.Geological Institute, Russian Academy of SciencesMoscowRussia

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