Albion’s Ænigma

  • Mark A. S. McMenamin
Part of the Springer Geology book series (SPRINGERGEOL)


The enigmatic Middle Devonian chordate Palaeospondylus gunni from the the Achannaras Slate Quarry, Caithness, Scotland, has recently been reinterpreted as a member of the Cyclostomata (the group that includes living jawless fishes). If this interpretation is correct, then Palaeospondylus either retains a vertebral column as a vestigial organ, or represents a remarkable case of skeletal homoplasy convergent on bony fishes. The ‘hard cartilage’ of Palaeospondylus may be a unique biomaterial restricted to the Devonian lifespan of this enigmatic genus.


Palaeospondylus Dipterus Cyclostomata Sclerotome Hagfish Cephalochordates 


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© Springer International Publishing AG 2018

Authors and Affiliations

  • Mark A. S. McMenamin
    • 1
  1. 1.Department of Geology and GeographyMount Holyoke CollegeSouth HadleyUSA

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