A revised morphology matrix provides an explicit phylogenetic hypothesis across sampled Heterostraci. The topology does not convert stratigraphic sampling into an exact group origin, extinction date or ancestor sequence.
claim:taxon:heterostraciHeterostraci
A revised morphology matrix provides an explicit phylogenetic hypothesis across sampled Heterostraci. The topology does not convert stratigraphic sampling into an exact group origin, extinction date or ancestor sequence. This navigation entry is not a phylogeny or a complete taxon dossier.
Represented range443.8–393.3 Ma
Content packageearly-fishes
PBDBtxn:117963
Evidence boundary
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Claim ledger
The Heterostraci study matrix includes dated Silurian–Early Devonian occurrences, supporting a 443.8–393.3 Ma study-sample window; this is not a global FAD, LAD or ancestor sequence.
claim:taxon:heterostraci:range-boundaryKnown limits
- A missing branch or fossil occurrence does not imply biological absence. Internal nodes are not calibrated divergence estimates.
- PBDB mapping requires concept review because the pinned lineage is incompatible with the local expected parent Ostracodermi.
References
- A phylogeny for Heterostraci (stem-gnathostomes)Randle, E.; Keating, J.N.; Sansom, R.S. · 2025 · DOI 10.1002/spp2.70030
- 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