An early Cambrian agglutinated tubular lophophorate with brachiopod characters
2014 (English)In: Scientific Reports, ISSN 2045-2322, Vol. 4, no 4682, 1-7 p.Article in journal (Refereed) Published
The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen. et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagersta¨tte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long pedicle with coelomic space. The terminal bulb of the pedicle provided anchorage in soft sediment. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods.
Place, publisher, year, edition, pages
2014. Vol. 4, no 4682, 1-7 p.
ORIGIN OF LIFE, PALAEONTOLOGY, BIODIVERSITY, SYSTEMATICS
Research subject Ecosystems and species history
IdentifiersURN: urn:nbn:se:nrm:diva-866DOI: DOI: 10.1038/srep04682OAI: oai:DiVA.org:nrm-866DiVA: diva2:764615
ProjectsOrigin and early evolution of major animal clades in the Cambrian Period
FunderSwedish Research Council, VR 2009-4395Swedish Research Council, 2012-1658