Hegetotheriopsis sulcatus Kramarz and Paz, 2013

Pino, Santiago Hernández Del, Seoane, Federico D. & Cerdeño, Esperanza, 2022, New craniodental material of the typotherian notoungulates from the upper Oligocene of Mendoza, central-western Argentina and their taxonomical importance, Acta Palaeontologica Polonica 67 (4), pp. 983-997 : 990

Hegetotheriopsis sulcatus Kramarz and Paz, 2013

Fig. 3G .

Holotype: MACN Pv CH 2015, left portion of rostrum and palate with P1–M3.

Type locality: La Cantera, Chubut Province, Argentina.

Type horizon: Sarmiento Formation, Lower Miocene, Colhuehuapian SALMA.

Material.—MCNAM-PV 3852, left lower premolar (p4?) from Quebrada Fiera, Mendoza Province, Argentina, upper Oligocene, Deseadan SALMA.

Remarks.—Out of the two specimens from Quebrada Fiera reinterpreted by Kramarz and Bond (2017) as Hegetotheriopsis sulcatus , we agree with this determination for the m3 MCNAM-PV 4620. We add the lower premolar MCNAM-PV 3852 ( Fig. 3G ) to this species. It is similar to the p4 of Hegetotheriopsis sulcatus from the Lower Miocene of the Sarmiento Formation in Bryn Gwyn (Chubut Province), because the trigonid is subcircular and the slightly larger talonid is subtriangular, with the labial groove being perpendicular to the flat lingual wall ( Kramarz and Paz 2013: fig. 3), but it differs in having a deeper labial groove, a condition that could be due to the greater degree of wear of MCNAM-PV 3852.

Stratigraphic and geographic range —Upper Oligocene– Lower Miocene, Deseadan–Colhuehuapian SALMA; Mendoza, Río Negro , Neuquén, and Chubut provinces, Argentina .

Figures

Fig.3. Lower dentition (anterior to the left) of hegetotheriid notoungulates from Quebrada Fiera, Mendoza,Argentina; upper Oligocene, Deseadan SALMA. A–F. “Prohegetotherium schiaffinoi (Kraglievich, 1932)”. A. MCNAM-PV 5076, mandible with left and right p1–m3 in occlusal (A1), ventral (A3), and left labial (A4) views, occlusal detail of left p1–m3 (A2). B. MCNAM-PV 5086, right mandibular fragment with p3–m3 (reversed) in occlusal view. C. MCNAM-PV 5018, left mandibular fragment with p4–m3 in occlusal (C1) and lingual (reversed) (C2) views. D. MCNAM-PV 5019, left mandibular fragment with p4–m3 in occlusal view. E. MCNAM-PV 5083, left mandibular fragment with p3–m3 in occlusal view. F. MCNAM-PV 5022, left mandibular fragment with p4–m2 in occlusal view. G. Hegetotheriopsis sulcatus Kramarz and Paz, 2013, MCNAM-PV 3852, left premolar (p4?) in occlusal view. H, I. Prosotherium garzoni Ameghino, 1897. H. MCNAM-PV 5017, right mandibular fragment with p4–m3 (reversed) in occlusal view. I. MCNAM-PV 4992, right mandibular fragment with p4–m1 (reversed) in occlusal view.