Panolia eldii ( M'Clelland , 1842)

Suraprasit, Kantapon, Jaeger, Jean-Jacques, Chaimanee, Yaowalak, Chavasseau, Olivier, Yamee, Chotima, Tian, Pannipa & Panha, Somsak, 2016, The Middle Pleistocene vertebrate fauna from Khok Sung (Nakhon Ratchasima, Thailand): biochronological and paleobiogeographical implications, ZooKeys 613, pp. 1-157 : 33-36

Taxon classification Animalia Artiodactyla Cervidae

Panolia eldii ( M'Clelland, 1842)

Referred material.

A cranium with a right partial antler, DMR-KS-05-04-20-4; a right P2, DMR-KS-05-03-15-11; two left M1-DMR-KS-05-03-00-24 and DMR-KS-05-03-00-25; six M2-DMR-KS-05-03-00-23 (right), DMR-KS-05-03-30-5 (right), DMR-KS-05-04-3-4 (right), DMR-KS-05-03-30-6 (left posterior lobe), DMR-KS-05-03-27-7 (left), and DMR-KS-05-04-3-5 (left); five M3-DMR-KS-05-03-27-6 (right), DMR-KS-05-04-9-1 (right), DMR-KS-05-04-8-3 (right), DMR-KS-05-03-00-22 (left), and DMR-KS-05-04-9-2 (left); two left mandibles-DMR-KS-05-03-27-2 (with p2-m3) and DMR-KS-05-04-9-5 (with p2-m2); a right i1, DMR-KS-05-03-29-2; a right scapula, DMR-KS-05-06-24-4; a left humerus, DMR-KS-05-04-11-35; a right fragmentary humerus, DMR-KS-05-03-18-1 (proximal part); three radii-DMR-KS-05-03-31-10 (right), DMR-KS-05-04-11-3 (right), and DMR-KS-05-03-19-16 (left); a right metacarpus, DMR-KS-05-03-24-2; two right femora-DMR-KS-05-03-27-11 and DMR-KS-05-03-17-36; five fragmentary femora-DMR-KS-05-04-05-38 (right proximal part), DMR-KS-05-03-28-20 (right distal part), DMR-KS-05-03-00-119 (right distal part), DMR-KS-05-03-19-2 (right distal part), and DMR-KS-05-08-16-1 (left proximal part); three left metatarsi-DMR-KS-05-03-25-8, DMR-KS-05-03-28-17, and DMR-KS-05-03-15-15.

Material description.

Cranium and upper dentition: DMR-KS-05-04-20-4 is an incomplete cranium, lacking the whole anterior parts (nasal, jugal, palatine, and maxilla) (Fig. 19 A–C) (for measurements, see Appendix 4). This specimen is a juvenile individual according to the incompletely fused sutures. The basioccipital and basisphenoid are triangular in outline and have straight lateral edges (Fig. 19C), different from those of Axis , and as observed on the recent skull of Panolia eldii (e.g., MNHN-ZMO-1937-157, MNHN-ZMO-1944-307, MNHN-ZMO-2011-190, and NMW-2975). The foramina ovale of DMR-KS-05-04-20-4 are more circular and open more anteriorly than those of Axis . The right partial antler contains a half of the slender main beam, but lacks a brow tine entirely (Fig. 19A, B). The divergent angle between the main beam and the brow tine is of about 110°, similar to recent skulls of Panolia eldii (e.g., THNHM-M-125). The antler surface is smooth and the burr is poorly developed in relation to the ontogenetic stages. The preserved shed antler shows a typical character of Panolia eldii , whose main beams strongly project and curve laterally (Fig. 19A).

P2 exhibits a prominent medial crista which divides the fossette into two islands (Fig. 19D). The separated anterior fossette is larger than the posterior one. On the upper molars, the buccal styles, anterior cingula, and entostyles are distinct (for measurements, see Tab. 12). The entostyle is bifurcated (Fig. 19 E–H). The metaconule fold (spur) is poorly developed. The posterior lobe of the M3 is reduced in width (Fig. 19G, H). The buccal wall of the posterior lobe is oblique in occlusal view.

Mandibles and lower dentition: Two mandibles (DMR-KS-05-03-27-2: Fig. 19J, K and DMR-KS-05-04-9-5: Fig. 19L, M) are nearly complete, preserving the bodies with cheek tooth rows (for measurements, see Appendix 5). The first specimen also preserves a partial ramus and is more complete than the second one in which the mandibular body is broken.

An isolated i1 is spatulate (Fig. 19I). Lower premolars show more complex patterns compared to Axis (e.g., the bifurcation of the metaconid on the p3, the irregular shape of the posterior valley, and the presence of more developed pre- and postprotoconulidcristids) (Fig. 19K, L). Lower molars display well-developed anterior cingulids and stylids (for measurements, see Tab. 12). The m3 is characterized by the presence of a posterior ectostylid (Fig. 19K). The shape of the posterior lobe of the m3 resembles that of Axis axis .

Postcranial remains: postcranial bones include a scapula (Fig. 20A, B), humeri (Fig. 20 C–E), radii, a metacarpus (Fig. 20 I–K), femora (Fig. 20 O–Q), and metatarsi (Fig. 20 L–N). They are almost complete. We identify these postcranial bones based on the correlation of size and proportion with the extant specimens of Panolia eldii (Tab. 13, and Appendices 1, 6-10, and 12).

Taxonomic remarks and comparisons.

Several authors consider Eld’s deer as belonging to either the genus Cervus (e.g., Lekagul and McNeely 1988, Tougard 2001, Gruwier et al. 2015) or Rucervus (e.g., Grubb 2005). However, Groves and Grubb (2011) suggested that placement of the Eld’s deer in the genus Panolia is an acceptable alternative based on mtDNA analysis ( Pitra et al. 2004).

The shed antler of the Eld’s deer, Panolia eldii , is characterized by bow- or lyre-like shapes, long, noticeable, and laterally bending-main beams with a distal portion curving medially, and small ornamented branches of brow tines. The cheek teeth of Panolia eldii differ from those of Axis axis in having a larger size, a more complex wear pattern of the mesolingual conids on the p3, more developed anterior cingulids on the lower molars, and a posterior ectostylid on the m3. The Khok Sung specimens assigned to Panolia eldii are similar in morphology to the extant specimens. As demonstrated by the body mass estimation (Tab. 14) and scatter diagrams (Figs 21 and 22), Panolia eldii from Khok Sung is also comparable in size to recent populations, to that from Thum Wiman Nakin, and to some fossil species (e.g., Cervus kendengensis from the Pleistocene of Bangle and Kali Gedeh in Java). However, we suggest that some isolated teeth of cervids from Thum Wiman Nakin ( Tougard 1998) reveal an improper taxonomic identification. The P2 (TF 3371 and TF 4570), p2 (TF 3938, TF 3313, TF 3358, and TF 3983), p3 (TF 3373), and m2 (TF 4025), attributed to Panolia eldii , may belong to other cervids (possibly Rusa unicolor ) due to their larger sizes. Our identification thus confirms the existence of Panolia eldii in Thailand during the late Middle Pleistocene.