Chapter

Evolutionary Biology – Concepts, Biodiversity, Macroevolution and Genome Evolution

pp 193-219

Date:

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

  • José Antonio Gámez VintanedAffiliated withÁrea de Paleontología, Depto. de Geología, Fac. de Biológicas, Universitat de València Email author 
  • , Eladio LiñánAffiliated withÁrea y Museo de Paleontología, Depto. de Ciencias de la Tierra, Fac. de Ciencias, Universidad de Zaragoza
  • , Andrey Yu. ZhuravlevAffiliated withÁrea y Museo de Paleontología, Depto. de Ciencias de la Tierra, Fac. de Ciencias, Universidad de ZaragozaGeological Institute, Russian Academy of Sciences

* Final gross prices may vary according to local VAT.

Get Access

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.