Hyaenictitherium wongii ( Zdansky, 1924 )

Bonis, Louis de, 2005, Carnivora (Mammalia) from the late Miocene of Akkaşdağı, Turkey, Geodiversitas 27 (4), pp. 567-589 : 572-575

Hyaenictitherium wongii ( Zdansky, 1924)

Ictitherium hipparionum – Gaudry 1862 -1867: 68. — Major 1894: 27. — Mecquenem 1925: 50. — Krokos 1939: 160. — Beaumont 1964: 339. — Koufos 1980: 56.

Palhyaena hipparionum – Kittl 1887: 333. — Kretzoi 1938: 113.

Ictitherium wongii Zdansky, 1924: 73 .

Ictitherium x wongii – Kretzoi 1938: 113.

Hyaenalopex atticus Kretzoi, 1952: 21 .

Ictitherium (Palhyaena) hipparionum – Schmidt-Kittler 1976: 81.

Palhyaena wongii – Howell F Petter 1980: 584.

Thalassictis wongii – Solounias 1981: 71. — Werdelin 1988: 223.

Thalassictis mesotes Kurtén, 1985: 81 .

Hyaenotherium magnum Semenov, 1989: 94.

Hyaenotherium wongii – Semenov 1989: 105. — Werdelin F Solounias 1991: 33. — Bonis 1994: 21.

MATERIAL. — Mandible (AKK-115) with left c, p2-m2 and right c-p3.

BACKGROUND

Among the huge amount of material unearthed from late Miocene Chinese localities, a hyaenid smaller than Adcrocuta eximia but larger than Ictitherium viverrinum was described under the name Ictitherium wongii by Zdansky (1924). H. wongii is also intermediate between the two other species in its evolutionary trends, having a more cutting dentition than I. viverrinum but less than Adcrocuta . This species had been described outside China before Zdansky’s publication under different names especially as Ictitherium (or Palhyaena ) hipparionum (see above for this name) and later as Thalassictis wongii (see Werdelin F Solounias 1991 for synonymy) and finally as belonging to the new genus Hyaenotherium Semenov, 1989 with H. wongii as the type species. But in the Chinese late Miocene localities where H. wongii is most common, there is also another medium sized hyaenid Ictitherium hyaenoides Zdansky, 1924 , later included in the new genus Hyaenictitherium by Kretzoi (1938). The differences between wongii and hyaenoides have been clearly stressed by Werdelin (1988). At that time the former was attributed to the genus Thalassictis ( Werdelin, 1988) and then to Hyaenotherium Semenov, 1989 . But if the specific differences are quite clear, we doubt the generic separation between the two species. Hyaenictitherium hyaenoides is generally larger than H. wongii , the premolars are broader but the main cuspid of p4 is relatively smaller, the talonid of m1 is slightly smaller and m2 is a little shorter, the upper carnassial is quite similar to that of H. wongii but the upper molars are more reduced, especially M2. These features allow us to differentiate the species but are not so strong as to separate two genera. Werdelin put both in the same genus Hyaenictitherium (in Zhang et al. 2002 and pers. comm.) and this is also my own o p i n i o n (B o n i s 2 0 0 4). A m a n d i b l e f r o m Akkaşdagwı with the left ramus, part of the right one and isolated teeth of the same individual belongs to this species.

DESCRIPTION ( FIGS 6 ; 7 )

The mandible is broken in front of the p2 but the ramus is quite complete except for a part of the condyle that is missing ( Fig. 6 ). The corpus is relatively deeper than that of I. viverrinum but less than that of Adcrocuta . The depth increases from the level of p2 to m1 and then decreases to the ramus, so the lower profile shows a bump under m1. A mental foramen is situated anteriorly under the mesial root of p2. The coronoid process is moderately elevated and the masseteric fossa is deep. The condyle is situated 2 cm above the short gonial process.

The corpus bears the alveolus of the canine and of the single rooted p1. The premolars are elongated and have a horizontal wear facet on the tip of the main cuspid. The p2 is asymmetric without any accessory cuspid. There are a very small mesial and a small distal accessory cuspids on p3. The accessory cuspids are more developed on p4 which has also a small linguo-distal accessory cusp like that of Ictiherium viverrinum but less developed. There is no clearly distinct distal crest. The proportions of the lower carnassial differ from that of I. viverrinum in having a short- er talonid relative to the trigonid. The metaconid is also more reduced. The single rooted m2 has an oval occlusal outline. It is completely worn and it is impossible to see the morphology of the crown.

The characters of this dentition and the measurements (Appendix: Table 1) fit quite well with H. wongii from China ( Zdansky 1924; Werdelin 1988). This species has been recovered from China to Greece and has previously been described from Turkey (Bonis 1994; Viranta F Werdelin 2003). A logarithmic comparison ( Fig. 7 ) shows that the dimensions of the Turkish fossil are closer to those of H. wongii but the differences between the two Chinese species are slight and some specimens could be difficult to identify.

Genus Thalassictis Gervais ex. Nordmann, 1850

The genus Thalassictis has been created by Gervais from drawings coming from a manuscript of Nordmann which was published later ( Nordmann 1858). So the two names, Gervais and Nordmann, must be associated. Thalassictis was often mixed with Ictitherium (see above the discussion for Ictitherium ).

Figures

FIG. 6. — Hyaenictitherium wongii (Zdansky, 1924), left hemi-mandible AKK-115, Akkaşdağı, late Miocene (Turolian), Turkey; A, buccal view; B, lingual view. Scale bar: 5 cm.

FIG. 7. — Logarithmic comparison of AKK-115 with specimens of Hyaenictitherium wongii (Zdansky, 1924) and H. hyaenoides Zdansky, 1924 from China (data from Werdelin). Abbreviations: b, breadth; L, length; Ltrig, length of the trigonid.