Middle Cambrian cystoid (sensu lato) stem columnals from Bornholm, Denmark

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Abstract
A rich material of echinoderm fragments from two Middle Cambrian stratigraphical levels on Bornholm are preserved due to phosphatization of the original calcitic stereom. Preservation of echinoderms in this way.sbd.no previously recorded from the Middle Cambrain.sbd.permits detailed analysis of the three-dimensional stereom structure. Identifiable are fragments of stylophorans and eocrinoids. Stem columnals, most likely from eocrinoids, show a wide and advanced morphological variation indicating articulation similar to that of crinoids. The material from the Exsulans Limestone/Kalby marl (Ptychagnostus gibbus Zone) represents stem-bearing cystoids older than Akadocrinus from Bohemia. The Andrarum Limestone (Solenopleura brachymetopa Zone) contains echinoderm fragments from a higher stratigraphical level, a level correlatable with that from which the oldest North American stem-bearing cystoid, Eustypocystis, has been recorded.