Follow named specimens from a Permian stem batrachian to a provisional Oligocene crown-caecilian record without merging total groups, crowns, direct ancestry or global first appearances.
Each step names its evidence claims, with references below. Interactive Explorer states are available in the full application; the narrative remains an editorial synthesis.
One Gerobatrachus holotype combines frog-like and salamander-like characters in the original tree, but it is not crown Batrachia or a direct ancestor.
A proposed topology and a specimen occurrence are narrower than the origin of living amphibians.
claim:event:kungurian-gerobatrachus-stem-batrachianμCT reveals caudal vertebrae and a long trunk in the unique Triadobatrachus holotype, supporting stem Salientia rather than crown Anura or specialized jumping.
Historical provenance and current numerical chart boundaries remain visibly separate.
claim:event:early-triassic-triadobatrachus-ctAt least 76 Funcusvermis individuals from a dated bonebed support Gymnophionomorpha while remaining outside crown Gymnophiona.
A total-group occurrence cannot set the crown-group range.
claim:event:norian-funcusvermis-stem-caecilianPKUP V0601–V0606 support an Oxfordian salamandroid record; the zircon age comes from overlying rock and neoteny is inferred.
Association strengthens anatomy while leaving age and developmental interpretation bounded.
claim:event:oxfordian-beiyanerpeton-salamandroidDGM 1462-R supports an Oligocene caecilian compared with living Typhlonectidae, but formal phylogenetic testing and an unambiguous family synapomorphy are absent.
The crown display bound is deliberately low-confidence and revision-ready.
claim:event:oligocene-ymboirana-crown-caecilian