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The stem and holdfast of Amygdalocystites florealis Billings, 1854 (Paracrinoidea): lifestyle implications

Published online by Cambridge University Press:  20 May 2016

Thomas E. Guensburg*
Department of Geography and Earth Science, Campus Box 1459, Southern Illinois University, Edwardsville 62026


Most fossil echinoderms are unknown as complete skeletons because they have easily disarticulated appendages. This is the case of paracrinoids, which have a ruggedly constructed theca but fragile brachioles and attachment structures. In their monographic review ofparacrinoids, Parsley and Mintz (1975) figured only one species (Comarocystites punctatus Billings, 1854) showing essentially complete skeletal morphology. Paracrinoids have no good modern analogues and therefore the task of evaluating their lifestyles is complicated.

Paleontological Notes
Copyright © The Paleontological Society 

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