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A pyritized polychaete from the Devonian of Ontario
Una C Farrell1, Derek E G Briggs
1Department of Geology and Geophysics, Yale University, PO Box 208109, New Haven, CT 06520-8109, USA.
Proceedings. Biological Sciences
|May 4, 2007
Summary
A new fossil polychaete, Arkonips topororum, was discovered in the Middle Devonian Arkona Shale. This exceptionally preserved specimen offers insights into early annelid anatomy and the potential of the Arkona Shale for soft-tissue preservation.
Area of Science:
- Paleontology
- Marine Biology
- Evolutionary Biology
Background:
- The Arkona Shale (Middle Devonian) is a fossil-rich Lagerstätte in Ontario, Canada.
- Polychaetes are a diverse group of segmented worms with a long fossil record.
- Exceptional preservation of soft tissues in fossils is rare but provides invaluable anatomical data.
Purpose of the Study:
- To describe a new species of polychaete from the Arkona Shale.
- To analyze the three-dimensional preservation of Arkonips topororum.
- To determine the phylogenetic placement of Arkonips topororum within Polychaeta.
Main Methods:
- Geological and paleontological analysis of a fossil specimen.
- Detailed morphological examination of prostomium, trunk appendages, and pygidium.
- Phylogenetic analysis based on morphological characters.
Main Results:
- A new polychaete species, Arkonips topororum, is described from the Middle Devonian Arkona Shale.
- The specimen exhibits remarkable three-dimensional preservation, including antennae, palps, tentacular cirri, biramous parapodia with chaetae, and a pygidium.
- Arkonips topororum is placed within the Palpata, Aciculata, crown group Phyllodocida.
Conclusions:
- Arkonips topororum represents a significant addition to the known Devonian polychaete fauna.
- The exceptional preservation of this specimen underscores the Arkona Shale's potential for yielding further soft-tissue fossils.
- This discovery enhances our understanding of polychaete evolution and paleoecology during the Devonian period.
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