Prostrepsiceros cf. vinayaki ( Pilgrim, 1939 )

Kostopoulos, Dimitrios S. & Bernor, Raymond L., 2011, The Maragheh bovids (Mammalia, Artiodactyla): systematic revision and biostratigraphiczoogeographic interpretation, Geodiversitas 33 (4), pp. 649-708 : 673-674

publication ID	https://doi.org/ 10.5252/g2011n4a6
persistent identifier	https://treatment.plazi.org/id/03EE374D-575D-C95E-FD72-FB8AFBD4FC22
treatment provided by	Marcus
scientific name	Prostrepsiceros cf. vinayaki ( Pilgrim, 1939 )
status

Treatment

Prostrepsiceros cf. vinayaki ( Pilgrim, 1939) ( Fig. 15 View FIG )

Gazellinae? gen. indet. (aff. Helicotragus ) vinayaki Pilgrim, 1939: 42 , pl. 1, fig. 10.

Prostrepsiceros houtumschindleri – Gentry 1971: 263 partim.

TYPE LOCALITY. — Nila-Dhok Pathan, Siwaliks, India (late Miocene).

MATERIAL EXAMINED. — MNHN.F: basal part of horncore MAR1005, 1003; p2-m3, MAR3145 sin ( Mecquenem 1925: pl. VI, fig. 2 as Oioceros rothii ), MAR1391 dex. — NHMW: right horn-core A4900.

DESCRIPTION AND REMARKS

This poorly known spiral-horned antelope, never previously reported from Maragheh is represented in the MNHN.F collection by a couple of basal horncore fragments with frontals, labelled as Antilopinae

Kostopoulos D. S. & Bernor R. L.

indet. One more, nearly complete horn-core in Vienna, so far attributed to P.houtumschindleri ( Gentry 1971) is further referred to Prostrepsiceros cf. vinayaki herein. Two mandibular rami in MNHN.F, one of them (MAR3145) previously ascribed to Oioceros by Mecquenem (1925: pl. VI, fig. 2) are assigned here to P. cf. vinayaki as well ( Table 5).

The horn-cores are extremely compressed with strong anterior keel, which in the distal part may be associated or replaced by a relatively deep furrow with irregular rims (MAR1003; NHMW A4900) ( Fig. 15 View FIG ; Table 11). The insertion of the horn-cores on the frontals is very oblique with the great basal axis of the horn-core almost perpendicular to the sagittal plane ( Fig. 15B, E View FIG ). The cross-section is elongated elliptical with the anterior keel in medial position. There is no posterior keel and the strongly convex posterior surface of the horn-core bears some strong longitudinal furrows. From the base to the top, the horn-core curves slightly posterolaterally forming an open spiralling of less than one complete coil. The median face of the horn-cores is weakly convex and the lateral one strongly convex. The supraorbital foramina open into an elongated depression. The pedicles are short and the frontoparietal suture passes just behind them.

Although the general appearance of the described horn-cores is similar to that of Prostrepsiceros houtumschindleri from the same area, the orientation of the horn-core basal axis ( Fig. 14A View FIG ) and the development of a strong anterior keel prevent referral to the same species. These horn-cores appear also to be 14-17% smaller in basal dimensions than those of P. houtumschindleri . Their morphology strongly resembles that of Prostrepsiceros vinayaki ( Pilgrim, 1939) and Sivoreas eremita Pilgrim, 1939 , both originally known from Siwaliks, Pakistan. Following Made & Hussain (1994), P. vinayaki differs from S. eremita in the more openly spiralled and weaker torsioned horn-cores, flaring strongly out, the less developed posterior keel, and the larger supraorbital pits. Hence, the Maragheh antelope matches better the Indo-Pakistani P. vinayaki , which appears, however, to be about 35% smaller in horn-core basal dimensions ( Table 11).

The dental morphology of the two available lower toothrows tentatively referred to this species is very similar to that of P. houtumschindleri but about 10% smaller and with rather shorter premolar row (47.0-51.6% of the molars instead of 53.0-58.0% in P. houtumschindleri ) ( Table 5). Furthermore, basal pillars occur only on m1, the goat fold is less marked than in P. houtumschindleri and the distinction between the paraconid and the parastylid on the p3 and p4 is less clear.