Burgessomedusa specimens preserve a large bell, more than ninety marginal tentacles and internal radial structures consistent with a free-swimming medusozoan by the middle Cambrian.
claim:event:burgessomedusa-swimming-medusaA macroscopic free-swimming medusa from the middle Cambrian Burgess Shale
Moon, J.; Caron, J.-B.; Moysiuk, J.
Year2023
Source roleprimary-study
DOI / ID10.1098/rspb.2022.2490
Fitness and scope
taxonomy · range · morphology · ecology
Describes Burgessomedusa from Raymond Quarry specimens and uses preserved bell, tentacles and internal anatomy to constrain a medusozoan interpretation.
Claim ledger
Raymond Quarry Burgessomedusa specimens preserve a bell, marginal tentacles and radial structures consistent with a swimming medusozoan; this middle-Cambrian sample is not the first appearance of all medusae.
claim:taxon:burgessomedusaBurgessomedusa is displayed at 506–504 Ma only as the Raymond Quarry specimen interval described for the genus; it is not a crown-medusozoan FAD, direct ancestor or global continuous duration.
claim:taxon:burgessomedusa:range-boundary-rc50Moon et al. describe Burgessomedusa phasmiformis from Raymond Quarry and recover a medusozoan affinity; exact placement among stem cubozoans, stem Acraspeda and alternatives remains model-dependent.
claim:taxon:burgessomedusa:taxonomyThe Raymond Quarry sample includes 182 specimens, with a cuboidal umbrella up to about 20 cm high, more than 90 short marginal tentacles and preserved internal features.
claim:taxon:burgessomedusa:morphologyThe described Burgessomedusa material is from Raymond Quarry in the Burgess Shale of British Columbia, Canada; this is a locality claim, not a global distribution.
claim:taxon:burgessomedusa:biogeographyBell shape and specimen associations provide indirect support for free swimming and a possible nektobenthic predatory habit, not observed feeding or measured swimming performance.
claim:taxon:burgessomedusa:ecology