Cantarius ohei, Schwarzhans & Aguilera & Scheyer & Carrillo-Briceño, 2022

Schwarzhans, Werner W., Aguilera, Orangel A., Scheyer, Torsten M. & Carrillo-Briceño, Jorge D., 2022, Fish otoliths from the middle Miocene Pebas Formation of the Peruvian Amazon, Swiss Journal of Palaeontology (2) 141 (1), pp. 1-15 : 4-5

publication ID	https://doi.org/10.1186/s13358-022-00243-5
persistent identifier	https://treatment.plazi.org/id/03DA87A9-FF98-5919-FCDF-5854FAB98C44
treatment provided by	Felipe
scientific name	Cantarius ohei
status	sp. nov.

Treatment

Cantarius ohei n. sp.

Figure 2A–F View Fig

Holotype. PIMUZ A/I 5001, Pebas Fm., middle Miocene, Iquitos (layer VI), Peru.

Etymology. Named after Fumio Ohe (Seto City, Japan) in recognition of his contribution to the study of fossil fish otoliths and interest in ariid catfishes.

Diagnosis. Te combination of extremely thick lapillus otolith, regularly subquadrangular outline, reduced antero-mesial projection, posterior obtuse angle at the posterior margin, and large mesial inward curvature distinguishes this species from other Ariidae species.

Description. Te lapillus otolith is regularly oval to subquadrangular and extremely thick. Anterior margin slightly oblique and in antero-distal projection passes beyond antero-mesial projection. Caudal margin forming an obtuse angle at its tip. Antero-mesial projection reduced and forming a continuous arch with the most antero-distal margin of the otolith. Umbo located on anterior part of dorsal surface. Both dorsal and ventral surfaces strongly convex. Pseudocauda of mesial shallow depression forming an arch and expanding posteriorly. Mesial inward curvature forming a large and well-developed wedge oriented posteriorly. Ratio lapillus length to width: 1.3. Ratio lapillus length to thickness: 2.0.

Discussion. Both Cantarius species are associated with the same outcrop section in the Miocene Pebas Wetland System at the Telefunkenstation (telegraph station), C. nolfi in layers I and C. ohei n. sp. in layer VI. We assume that these records represent only a first glimpse of the fossil freshwater ariid diversity that can be expected in the sedimentary basins of the western Amazon.