While not formally synonymized by Coppard & Lessios (2017), it is clear from their text that they consider E. micropora cocosei as synonym of E. micropora.
Coppard, S.E. & Lessios, H.A. (2017). Phylogeography of the sand dollar genus Encope: implications regarding the Central American Isthmus and rates of molecular evolution. <em>Scientific Reports.</em> 7(1): 11520.