Sinotragus undetermined

Kostopoulos, Dimitris S. & Karakütük, Seval, 2015, Late Miocene bovids from Şerefköy- 2 (SW Turkey) and their position within the sub-Paratethyan biogeographic province, Acta Palaeontologica Polonica 60 (1), pp. 49-66 : 60-61

cf. Sinotragus sp.

Fig. 14 .

Material. —MYŞE PV-1409, partial left upper tooth row preserving only P2–P3; MYŞE PV-2553, left mandibular body with p2–m3; MYŞE PV-2567, right mandibular body with p2–m3. All from Şerefköy-2, Turkey, Late Turolian (Late Miocene).

Description. —The only maxillary fragment preserves P2 and P3 ( Fig. 14C , SOM 3: Table 1 ). P2 is weekly bilobed lingually and has a trapezoidal occlusal outline, with a weak anterior style, strong anterolabial cone, posterolabially protruding posterior style, and distolingually broadened posterolingual crista. P3 is subrectangular in occlusal view and bears strong labial styles and ribs, as well as a weak lingual groove dividing the distolingually expanded lingual cone ( Fig. 14C ). A weak notch on the distal wall of the tooth emphasises the posterior style. Traces of enamel on the distal occlusal surface suggest that the tooth originally had an additional distal fossa or a strong central fold.

The lower premolar row is moderately short compared to the molars, with premolar/molar ratios of 56.7% and 57.9% (n = 2) ( Fig. 14A, B , SOM 3: Table 2 ). The lower premolars are narrow and short. The p2 lacks an anterior conid, but bears an anteriorly located mesolingual conid and a week anterior stylid. The mesolingual conid of p3 is elongated and directed posteriorly. The posterolingual conid of p3 is strong. The anterior conid and stylid are equally developed and fuse together during advanced stages of wear. The anterior valley is open. Unlike p3, p4 is distinctly molarised ( Fig. 14A, B ). On the lingual wall, the anterior valley closes quickly during wear and the mesolingual conid fuses with the posterior conid and stylid. Labially, there is a well-developed posterolabial conid. The lower molars bear a strong ectostylid and have a gently undulating lingual wall covered by cement.The third lobe of m3 is relatively high and large, oval in occlusal view, and bears a convex entoconulid.

Remarks.—The finely rippled enamel, advanced p4 morphology, reduced premolars, build-up of cement on the molars, large third lobe of the m3, strong basal pillars, and weak development of the lingual stylids and ribs exclude this taxon from the Late Miocene Antilopini sensu stricto. Together with the inferred additional posterior fossa on P3, the distolingual widening of the lingual cone and the distolabial development of the posterior style on P2 and P3 are reminiscent of the considerably larger Urmiatherium intermedium Bohlin, 1935 , U. polaki Rodler, 1889 , and Plesiaddax depereti Bohlin, 1935 . However, the Şerefköy-2 taxon differs from the large-sized Late Miocene “ovibovines”, but resembles the smaller U. rugosifrons from Samos ( Kostopoulos 2009a: 371), in the development of the third lobe on m3, as well as the weak buccolingual compression of the lower molars and the degree of fusion of their lobes. U. rugosifrons and the Şerefköy-2 species furthermore share a comparably reduced premolar row. However, the former species is still about 30–35% larger and characterised by less derived lower premolars.

Although the available data are not sufficient for definite conclusions, it is worth mentioning that a right upper tooth row from Muğla (MNHN TRQ 974) resembles the material from Şerefköy- 2 in its size and premolar morphology. The molars of TQR 974 considerably differ from those of Urmiatherium and Plesiaddax , but resemble those of Sinotragus wimani Bohlin, 1935 from China ( Bohlin 1935: pl. 16: 8, 9). Unfortunately, the lower dentition of Si. wimani is unknown, preventing a direct comparison with Şerefköy-2. TRQ 974 is accompanied by a frontlet from the same region (MNHN TRQ 973), which, based on its morphology and size, likely represents a female Si. occidentalis Geraads, Güleç, and Kaya, 2002 . This species is well-documented in Muğla by cranial, but not dental, elements ( Geraads et al. 2002). Given the particular dental characters of TRQ 974, the similar size of TQR 974 and TRQ 973, and their common geographic provenance, we speculate that both specimens belong to Si. occidentalis . In addition, we tentatively refer the Şerefköy- 2 specimens to Sinotragus based on their similar dental morphology.

Figures

Fig. 14. The bovid artiodactyl cf. Sinotragus from Şerefköy-2 (Turkey), Late Turolian (Late Miocene). A. Left mandibular ramus (MYŞE PV- 2553) in labial (A 1) and lingual (A 2) views. B. Right mandibular body MYŞE PV-2567) in occlusal view. C. Left upper P2–P3 (MYŞE PV-1409) in occlusal view.