New hyolith specimens from the early Cambrian (Stage 4) of the Three Gorges area, western Hubei Province are described and assigned to the species . are preserved in two taphonomic modes: casts in silty mudstone revealing gross morphology and some soft parts, and internal molds in calcareous pelites, which exhibit new morphological details of the conch and operculum. SEM and Micro-CT analyses show that preserve well-developed platy clavicles and cardinal processes on the interior of the operculum composed of rod-shaped tubular elements. This observation and the distinct cardinal and conical shields of the operculum indicate that could be placed within the Family Paramicrocornidae, most recently established as a group of hyoliths closely related to hyolithids.
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| http://dx.doi.org/10.3390/biology11060875 | DOI Listing |
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