Reconstruction, composition and homology of conodont skeletons – a response to Agematsu et al. 2018

[First paragraph] AGEMATSU et al. (2018) commented on our recent paper about testing hypotheses of element loss and apparatus stability in the apparatus composition of complex conodonts (Zhang et al. 2017). They take issue not with our approach, but with our specific hypothesis concerning the skeletal apparatus of Hindeodus parvus. We proposed that,in marked contrast to the remarkable anatomical conservatism exhibited by ozarkodinid conodonts, which seem not to vary their 15 element ‘dental formula’ over a period in excess of 250 million years, H. parvus had only 13 elements, lacking 2 elements from the posterior P domain of the apparatus.Our paper presents an hypothesis of homology for the skeletal elements of H. parvus that Agematsu et al. (2018) argue is incorrrect, based on three lines of reasoning