Abstract
Summary. The large number of species assigned toTriarthrusGreen are here allocated to three genera - ten species to a revisedTriarthrusGreen (late Caradoc-Ashgill), thirteen species to a revisedPorterfieldiaCooper (Arenig-Llandeilo), and five species toBienvilliaClark (Tremadoc-Arenig).Triarthruslacks an anterior border furrow on the cranidium; this furrow is confined to the yoked cheeks. BothPorterfieldiaandBienvilliahave an anterior border furrow on the cranidium; these genera are distinguished primarily on the length of the preglabellar field.
Full Text 
Sign-in/Register to access full text options
Sign-in/Register to access full text options 
Published version (
Free)
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
