The oldest teleosts (Teleosteomorpha): their early taxonomic, phenotypic, and ecological diversification during the Triassic

Named specimens of Pseudopholidoctenus, Barschichthys and Ruedersdorfia from the approximately 244 Ma Rüdersdorf locality document taxonomic, anatomical and ecological disparity on the teleosteomorph stem; they do not establish a global fossil first appearance of crown Teleostei or a synchronous worldwide radiation.

Pseudopholidoctenus germanicus is a named stem teleosteomorph established from the Rüdersdorf type material, including holotype MB.f.18641 and paratypes MB.f.19904–19906.

The Pseudopholidoctenus germanicus material comes from the Rüdersdorf opencast mine in the Central European (Germanic) Basin, Germany; this locality does not establish a global distribution.

The cited description records an aquatic fish from a marine restricted-basin setting, but it does not establish a species-specific diet, locomotor performance or trophic guild for Pseudopholidoctenus germanicus.

Pseudopholidoctenus germanicus has a fused, ornamented skull roof, large square-like scutes before the epaxial caudal lobe, fewer than 18 principal caudal rays and no hypaxial procurrent rays in the diagnosis.

The displayed approximately 244 Ma point bounds the lower Anisian Rüdersdorf sample of Pseudopholidoctenus germanicus and is not a global teleosteomorph or teleost first appearance.

Barschichthys ruedersdorfensis is a named stem teleosteomorph and type species of Barschichthys, based on holotype MB.f.19907 and paratypes MB.f.19908–19909 from Rüdersdorf.

The Barschichthys ruedersdorfensis type and referred specimens come from the Rüdersdorf opencast mine in the Central European (Germanic) Basin, Germany; no global distribution is inferred.

Barschichthys ruedersdorfensis is recorded from the study's marine restricted-basin setting, but its species-specific diet, locomotor performance and trophic guild remain unresolved.

Barschichthys ruedersdorfensis has a broad lobated skull-roof margin lacking the triangular nasal region, a fused ornamented cranial plate, ganoid scales and a long lower jaw with small conical teeth.

The displayed approximately 244 Ma point bounds the lower Anisian Rüdersdorf sample of Barschichthys ruedersdorfensis and is not a global teleost first appearance.

Ruedersdorfia berlinensis is a named stem teleosteomorph placed as Teleosteomorpha incertae sedis, based on holotype MB.f.19910 and paratypes MB.f.14888 and MB.f.19911.

The Ruedersdorfia berlinensis type and referred skull roofs come from the Rüdersdorf opencast mine in the Central European (Germanic) Basin, Germany; this occurrence does not establish global distribution.

Ruedersdorfia berlinensis is associated with the study's marine restricted-basin fossil setting, but the skull-roof-only sample does not establish diet, locomotion or a trophic guild.

Ruedersdorfia berlinensis has a fused skull roof with a nearly equal orbital and postorbital region, a short nasal region and middle pitline, and characteristic ganoine ornamentation.

The displayed approximately 244 Ma point bounds the lower Anisian Rüdersdorf sample of Ruedersdorfia berlinensis and is not a global teleosteomorph or teleost first appearance.