Postibullinid edrioasteroids are a small clade of discoidal edrioasteroids that are locally common members of Devonian to Pennsylvanian, shallow marine, hard substrate faunas in North America and Europe. A small discoidal theca, narrow, highly elevated ambulacral cover plates, a highly elevated anal pyramid, and in many forms a posterior oral protuberance characterize this clade (Bell, 1976b; Sumrall et al., 2000). Here we describe the oldest known postibullinid, Pyrgopostibulla belli n. gen. and sp., a species that differs from other postibullinids by having a well-developed pedunculate zone and a complex, five-plate pattern of ambulacral cover plates. A dense...

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