Paratrygon orinocensis

Loboda, Lasso, Rosa & De Carvalho, 2021



Classification: Elasmobranchii Myliobatiformes Potamotrygonidae

Reference of the original description
Loboda, T.S. & Lasso, C.A. & Rosa, R.S & de Carvalho, M.R. (2021)
Two new species of freshwater stingrays of the genus Paratrygon (Chondrichthyes: Potamotrygonidae) from the Orinoco basin, with comments on the taxonomy of Paratrygon aiereba. Neotropical Ichthyology, 19(2), Article e200083

Types
Paratrygon orinocensis
Holotype: IAvH: P-11939; Paratype: IAvH: P-12449; IAvH: P-12448; IAvH: P-11940; IAvH: P-12439; MZUSP: 117220; USNM: 233944;

Images of types

Description :


Citation: Paratrygon orinocensis Loboda, Lasso, Rosa & De Carvalho, 2021: In: Database of modern sharks, rays and chimaeras, www.shark-references.com, World Wide Web electronic publication, Version 12/2024

Please send your images of "Paratrygon orinocensis" to info@shark-references.com

Paratrygon orinocensis Loboda, Lasso, Rosa & De Carvalho, 2021, holotype, IAvH-P 11939, adult female, 286 mm DW, from Orinoco river. A. dorsal and B. ventral views. © Loboda, Lasso, Rosa & De Carvalho, 2021
Short Description
Original diagnosis of LOBODA, LASSO, ROSA & DE CARVALHO, 2021 [29758]: Paratrygon orinocensis is distinguished from congeners by a combination of characters. Paratrygon orinocensis without lateral rows of thorns on tail (vs. P. aiereba and Paratrygon parvaspina with lateral rows of thorns on tail). Dermal denticles on the central region of the disc of P. orinocensis have wide and high crowns, presenting a central coronal plate very similar morphologically to its lateral coronal ridges, which in adults can be more than 12 (vs. P. aiereba and P. parvaspina that have small dermal denticles on the central disc, with high and narrow crowns presenting higher and pointed central coronal plates surrounded by minor, pointed or rounded lateral coronal ridges, which in turn vary between three and six). Paratrygon orinocensis has 22‒35/20‒29 teeth (vs. P. aiereba with 16‒26/14‒20, and P. parvaspina with 31/19‒22); central teeth of P. orinocensis with more developed and high cusps than P. aiereba and P. parvaspina. In P. orinocensis the spiracles are small and triangular, with mean length 5.6% DW [4.5‒7.9% DW] (vs. quadrangular and larger spiracles in P. aiereba, with mean length 6% DW [4.4‒11.6% DW], and very small and quadrangular spiracles in P. parvaspina with mean length 5.2% DW [4.9‒5.8% DW]. Paratrygon orinocensis has a short and straight spiracular process with developed and numerous dermal denticles (vs. larger and knob shaped spiracular process that almost covers the spiracle aperture and with some small dermal denticles in P. aiereba, and an extremely short and reduced spiracular process in P. parvaspina that is more perceptible in adult specimens, with few dermal denticles). Paratrygon orinocensis has a minute rostral projection (vs. P. aiereba that has a relatively large rostral projection, and P. parvaspina that has a large and circular rostral projection).

Distribution
Endemic to the Orinoco basin, [29758]

Size / Weight / Age
TL (max): 866 mm [29758]

Habitat
freshwater [29758]

Dentition
Teeth triangular, large, cuspidate, arranged in quincunx in both jaws, presenting few differences in size between teeth from central and lateral rows, but central teeth slightly greater. Adult specimens possess pointed and high cusps, with teeth of central rows and in the lower jaw more developed. Tooth rows in adults 22‒35/20‒29, with exposed teeth in symphysis 2‒4/3‒4.[29758]

Remarks
shark-references Species-ID=16137;