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Updated: Feb 2, 2026

Acquisition and Semi-Automated Analysis of Respiratory Muscle Surface Electromyography
Published on: January 24, 2025
A well-preserved respiratory system in a Silurian ostracod
David J Siveter1, Derek E G Briggs2, Derek J Siveter3,4
1School of Geography, Geology and the Environment, University of Leicester, Leicester LE1 7RH, UK djs@leicester.ac.uk.
Abstract:
Ostracod crustaceans are diverse and ubiquitous in aqueous environments today but relatively few known species have gills. Ostracods are the most abundant fossil arthropods but examples of soft-part preservation, especially of gills, are exceptionally rare. A new ostracod, Spiricopia aurita (Myodocopa), from the marine Silurian Herefordshire Lagerstätte (430 Mya), UK, preserves appendages, lateral eyes and gills. The respiratory system includes five pairs of gill lamellae with hypobranchial and epibranchial canals that conveyed haemolymph. A heart and associated vessels had likely evolved in ostracods by the Mid-Silurian.
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