Santos, R.O.; Wilkinson, M.; Ribeiro, G.C.; Carvalho, A.B.; Zaher, H.
range · taxonomy · morphology · ecology · methods
CT-based primary description of holotype DGM 1462-R; Typhlonectidae assignment is based on comparative anatomy and remains to be tested in a formal phylogenetic analysis.
The approximately 25 Ma holotype of Ymboirana acrux was assigned to the living family Typhlonectidae by comparative anatomy, provisionally supporting a crown-Gymnophiona fossil record while formal phylogenetic testing and unambiguous family synapomorphies remain unavailable.
claim:taxon:gymnophiona:provisional-crown-recordCT-informed comparison of holotype DGM 1462-R supports an approximately 25 Ma aquatic caecilian assigned to Typhlonectidae, but damage, absent unambiguous family synapomorphies and pending formal phylogenetic testing make the crown placement provisional.
claim:event:oligocene-ymboirana-crown-caecilianThe Amphibian fossil evidence route navigation entity is source-linked only to the named specimen, dataset and analysis dossiers already cited by its range ledger. Its displayed span is a study-bounded route or sample envelope, not a biological taxon, ancestor sequence, global FAD/LAD or exact origin interval.
claim:taxon:amphibian-fossil-evidence-routeYmboirana acrux is documented by holotype DGM 1462-R from the Oligocene Tremembe Formation in Brazil's Taubate Basin. The partially preserved skeleton records this fossil occurrence, not the species's complete distribution, exact origin time or a global first appearance of aquatic caecilians.
claim:taxon:ymboirana