Project 1216: S. Zamora, A.B. Smith. 2012. Cambrian stalked echinoderms show unexpected plasticity of arm construction. Proceedings of the Royal Society B: Biological Sciences. 279 (1727):293-298.
Specimen: Gogia (unvouchered)
View: body

Abstract

Feeding arms carrying coelomic extensions of the theca are thought to be unique to crinoids among stemmed echinoderms. However, a new two-armed echinoderm from the earliest Middle Cambrian of Spain displays a highly unexpected morphology. X-ray microtomographic analysis of its arms shows they are polyplated in their proximal part with a dorsal series of uniserial elements enclosing a large coelomic lumen. Distally, the arm transforms into the more standard biserial structure of a blastozoan brachiole. Phylogenetic analysis demonstrates that this taxon lies basal to rhombiferans as sister-group to pleurocystitid and glyptocystitid blastozoans, drawing those clades deep into the Cambrian. We demonstrate that Cambrian echinoderms show surprising variability in the way their appendages are constructed, and that the appendages of at least some blastozoans arose as direct outgrowths of the body in much the same way as the arms of crinoids.


Read the article »

Article DOI: 10.1098/rspb.2011.0777

Project DOI: 10.7934/P1216, http://dx.doi.org/10.7934/P1216
This project contains
  • 1 Media
  • 2 Documents
  • 14 Taxa
  • 1 Specimen
Total size of project's media files: 30.75k

Download Project SDD File
Currently Viewing:
MorphoBank Project 1216

    Authors' Institutions

    • Natural History Museum, London

    • Universidad de Zaragoza



    Members

    member name taxa specimens media
    Jo Wolfe
    Project Administrator
    000
    MorphoBank Curator
    Full membership
    000
    Maureen O'Leary
    Full membership
    1411
    Andrew Smith
    Full membership
    000


    Project has no matrices defined.



    Project views

    type number of views Individual items viewed (where applicable)
    Total project views6657
    Media views1095Media search (945 views); M841621 (150 views);
    Documents list291
    Project overview436
    Bibliography243
    Views for media list1708
    Specimen list636
    Taxon list2248




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project15
    Project downloads5
    Document downloads9Cambrian echinoderm matrix (5 downloads); Cambrian echinoderm character list (4 downloads);
    Media downloads1M841621 (1 download);