A synthesis maps colony form, life cycle and medusa characters onto published hydrozoan phylogenies; the inferred gains and losses are comparative reconstructions rather than directly observed ancestral states.
claim:taxon:hydrozoaHydrozoa
A synthesis maps colony form, life cycle and medusa characters onto published hydrozoan phylogenies; the inferred gains and losses are comparative reconstructions rather than directly observed ancestral states. This navigation entry is not a phylogeny or a complete taxon dossier.
Represented rangeRange unavailable
Content packagesponges-cnidarians
PBDBtxn:4596
Evidence boundary
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Claim ledger
Hydrozoa has no supported scalar temporal range in the cited evidence: the character-evolution review does not document a diagnostic 520 Ma hydrozoan fossil or crown boundary, so the former 520–0 Ma display is withheld.
claim:taxon:hydrozoa:range-boundary-rc50Known limits
- A missing branch or fossil occurrence does not imply biological absence. Internal nodes are not calibrated divergence estimates.
References
- Character evolution in Hydrozoa (phylum Cnidaria)Cartwright, P.; Nawrocki, A.M. · 2010 · DOI 10.1093/icb/icq089
- Open Tree of Life web servicesOpenTreeOfLife Project
- The Paleobiology Database application programming interfacePeters, S.E.; McClennen, M. · 2016 · DOI 10.1017/pab.2015.39
- Denormalized occurrence and taxon tables of the Paleobiology DatabaseThe Paleobiology Database Community; Kocsis, Á.T. · 2026 · DOI 10.5281/zenodo.21620933