OBJECT DOSSIER · SMITHSONIAN OPEN ACCESS

Early echinoderm — Ctenocystis utahensis

SAGE Museum Deep Time scientific dossier

Artist / Creator

Jessica Utrup

Date / Period

Middle Cambrian · Lower Middle Cambrian.

Object Type

body fossil

Medium

original_fossil

About This Object

Geologic period: Middle Cambrian

Age: Lower Middle Cambrian.

Feeding: Feeding interpretation is based on the specialized anterior apparatus.

Locomotion: Interpreted as a free-living bottom-dwelling animal.

Body plan: Flattened flexible theca with near-bilateral symmetry and a ctenoid feeding apparatus.

Evidence: Body plates and feeding apparatus are fossil evidence. Mode of life is reconstructed from anatomy.

Why it matters: Ctenocystis shows how strange and experimental early echinoderm body plans were before familiar modern forms evolved.

Plain Language Identity: A primitive Cambrian echinoderm unlike modern starfish or sea urchins.

What You Are Looking At: A flattened body enclosed by skeletal plates with a distinctive comb-like feeding structure.

Ecosystem: Cambrian seafloor ecosystem.

Preservation: Skeletal body fossil.

Open Questions: Its appearance should not be forced into a modern starfish or sea-urchin body plan.

Source Urls: https://naturalhistory.si.edu/visit/virtual-tour/current-exhibits/deep-time-virtual-tour-fossil-list; https://pubmed.ncbi.nlm.nih.gov/17742852/

Enrichment Method: SAGE curated research pass; title and scientific name matched; evidence separated from inference

Scientific name: Ctenocystis utahensis

Evidence / representation: comparative_exact_taxon_visual

Why It Is In This SAGE Exhibit

comparative_exact_taxon_visual

Oceans Before Dinosaurs: The Rise of Complex Animal Life.

Provenance

Smithsonian Deep Time source scene: Early Life in the Ocean

Visual source institution: Wikimedia Commons

Exhibition History

Included in the SAGE Museum Dinosaurs & Deep Time staging exhibit.

Collection & Credit

Media license: CC0

http://creativecommons.org/publicdomain/zero/1.0/deed.en

Subjects & Themes

Ctenocystis utahensis Middle Cambrian body fossil Early Life in the Ocean Oceans Before Dinosaurs

ORIGINAL COLLECTION SOURCE

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