THE PIG PROPOTAMOCHOERUS PALAEOCHOERUS FROM THE UPPER MIOCENE OF GRYTSIV, UKRAINE

The suid from Grytsiv (= Gritsev) in Ukraine belongs to the genus Propotamochoe· rus. This genus was not yet known from the Miocene of eastem Europe. The Grytsiv suid is described and its significance is discussed within the palaeobiogeographical and stratigraphical framework of the genus Propotamochoerus. Grytsiv is geographically situated between three areas with different species of the genus: W Europe (P. palaeo· choerus), China (P. hyotherioides) and the Indian Subcontinent (P. hysudricus). In Euro· pe, P. palaeochoerus is replaced at the MN 9·10 boundary or early in MN 10 by a diffe· rent species of Propotamochoerus with affinities with P. hyotherioides or P. hysudricus. The fossils from Grytsiv extend the known range of P. palaeochoerus eastward into Ukraine.


Description and comparison
The 1 1 (PI. 1, fig.7) and 1 2 (PI. 1, fig.8) have crowns of an intermediate height.In Hyotheriinae and Cainochoerinae, the crowns are lower, in many Tetraconodontinae and Suinae, the crowns are of similar height, but in part of the Suinae, including Sus the crowns are higher.In the incisors with higher crowns the lower limits of the crown are not so clear; the enamel becomes thinner gradually, whereas in the Grytsiv incisors, the crowns have well marked limits.The labio-lingual diametre is long.It tends to be relatively less in the higher incisors.It is in the Dicoryphochoerini, as a stem group of the Sumae, that these changes start to take place.Within this group the type of incisor from Grytsiv is primitive.
The 1 3 (PI.1, fig. 6) reflects the changes described aboye.However, the situation is even more complex.In sorne lineages, that increase 1-2 crown height (eg.Hippopotamodon), this incisor also becomes higher, whereas in others (eg.Sus), the tooth is reduced in size, the crown is low and the morphology not well defined.In P. hyotherioides, the 1 3 has a much lower crown (Van der Made & Han, 1994, PI. 13, fig.5).
The Cm (PI. 1, fig. 5) has a section that resembles a isoscele triangle.In many suids, either the labial side «<scrofic canines») or the posterior side «<verrucosic canines») tends Fig. 4.-Bivariate plots of the upper incisors.Legend and provenance of data as in Figure 2.
to be narrow.P. palaeochoerus (dots in fig. 1) and the MN 11-13 Propotamochoerus (square) tend to have both sides equally wide or even the posterior side wider, whereas P. hysudricus (triangle) and P. hyotheriodes (stars) tend to have wider labial sides «<scrofic canines»).All three sides of the section of the canine are convexo This is a very typical morphology that occurs in P. palaeochoerus.while other suids tend to have the labial surface flat or with ridges.P. palaeochoerus and the suid from Grytsiv have relatively small canines.The isolated PI (PI.2, fig.3) and P 2 (PI.2, fig.5) are assigned with sorne reservations to this species, since there is no independent indication of the presence of a second species.They are small teeth, with, in particular in the PI' the protoconid placed much foreward, and with an inflated talonid shelf with only a faint indication of the protopostcristid.This morphology tends to be common in Tetraconodontinae.The small tetraconodontines Parachleuastochoerus crusafonti and Parachleuastochoerus huenermanni are often found in the same localities as P. palaeochoerus.The problem in recognition is that PI and P2 tend to be more or less rare teeth, and those that are known are often isolated.Therefore variation in morphology and size is not well known in these teeth.The two islolated teeth are tentatively assigned to P. palaeochoerus, but the possibility that they belong to one of the small Parachleuastochoerus species cannot be excluded.The P2 and P 3 (PI.2, figs. 1 & 4) have a flattened protoconid with anterior and posterior crests.In the P f in the mandibles, the protopostcristid is a better developed than in the isolated premolars.The P 4 (PI.2, figs. 1 & 4) has a metaconid that is placed close to and slightly behind the protoconid.Though the differences are small, the cusp is better developed than in the majority of the species of this genus and is similar in size and position to the metaconid of the P. palaeochoerus P 4 • The protoprecristid becomes rapidly lower away from the protoconid.The talonid has a well developed hypoconid, more or Iess in the middle.The tooth is of the Dicoryphochoerine type (sensu Schmidt-Kittler, 1971 and Van der Made & Moya-Sola, 1989).
The The MI and M 2 (PI. 1, fig. 1) have the typical suine morphology, though the crests or lobes are not as welI visible as in several of the younger genera of the Suinae.The M3 (PI. 1, fig. 2) has a simple third lobe consisting of a pentacone that is placed lingualIy of the axis of the tooth.In addition to this cusp, there is also a pentapreconule and sorne lateral wrinkles (formed by the pentaectocrista and pentaendocrista).
Sorne deciduous teeth and bones have the common suid morphology.
In figures 2 & 3 the DAP and DT of the teeth of the different species of Propotamochoerus.P. palaeochoerus (dots) and the Grytsiv (triangles) suid tend to have large first molars and P4, while the second molars are not so big, and the third molars are even smalI compared to the other species.The relative size of the third (and to sorne extend the second) molar reflects diet; larger or longer M3 suggest a more herbivorous diet.P. hyotherioides (stars), P. hysudricus (oblique crosses) and the European Propotamochoerus of MN 11-13 (crosses) seem to have relatively large M 3 and smalI P 4 compared to P. palaeochoerus (dots).

Discussion
The Vallesian suids inelude very small Cainochoerinae, lophodont Listriodontinae, Tetraconodontinae with an enlarged P4 with only one main cusp, Chinese Hyotheriinae with no paraendoconulid in the p4 and Suinae of the tribe Dicoryphochoerini.The morphology of the premolars suggests that the Grytsiv suid belongs to the Dicoryphochoerini, a tribe of the Suinae (Schmidt-Kittler, 1971; Van der Made & Moya-Sola, 1989).In a recent elassification, this tribe ineludes: Propotamochoerus (=Kory- nochoerus), Hippopotamodon (=Microstonyx), Eumaiochoerus, Kolpochoerus and Hylochoerus (Van der Made, 1997).All specíes of Hippopotamodon are much larger than the Grytsiv suid.Eumaiochoerus is an endemic of a Miocene island that included Toscane and Sardinia and has a number of peculiar features.Kolpochoerus and Hylochoerus are known only from Africa and are suids with a highly specialized dentition, with incisors with increased DMD relative to DLL, with very elongated M3 and with sorne tendency to increase hypsodonty.The suid from Grytsiv belongs to Propota- mochoerus.
Most of the species of Propotamochoerus were originally assigned to the genus Sus.This is for instance the case with P. palaeochoerus, which has intially been assigned to Sus and later to Hyotherium and Korynochoerus.Pickford (1988) stated that the species was very similar to Propotamochoer- us hysudricus and Van der Made et al. (1992) were possibly the first to place the specíes formally in Propotamochoerus, though the justification for that remained a long time in press (Fortelius et. al., 1996).The genus Propotamochoerus includes the following species: P. palaeochoerus, P. hysudricus, P. hyotherioides, P. wui, P. provincialis and a form that entered Europe either in MN 10 or MN 11 and that lived on till at least MN 13 (Pickford, 1988;Van der Made & Moya-Sola, 1989;Van der Made & Han, 1994;Fortelius et al., 1996).The limits of the geographical distribution of these species is not known.Pliocene P. provincialis has been described from Kuchurgan (Korotkevich, 1967(Korotkevich, , 1988) ) and Kvabevi (Vekua, 1972).Miocene Propotamochoer- us have not been cited from the area and the collection from Grytsiv is the first one in being described from the area that extends from the north of the Black Sea to the north of China.Grytsiv is thus in a position between the three areas from where the genus is well known.
P. wui is a very small species from the Late Miocene of China (Van der Made & Han, 1994) and is much smaller than the Grytsiv suid.
P. hysudricus.Pickford (1988) revised the Miocene Suids of the Indian Subcontinent and recognized only P. hysudricus.Skulls assigned to this specíes have either the parietal ridges wide apart and a straight dorsal profile or have these crests close together and a concave profile with the occipitals appearing as being elevated.It is the question, whether all this material represents one specíes, or whether there is a rupture like in Europe.Until this problem is resolved, we follow Pickford (1988) and treat the material as representing one specíes.
The material assigned here to P. hysudricus includes tooth rows with premolars, sorne isolated premolars, but no isolated molars.The material is predominantly from Dhok Pathan equivalent strata, or of unknown exact provenance.M 3 tend to have a  simple third lobe, but is relatively large.Whereas the MI and P4 tend to be smaller than in P. palaeochoerus, the M3, and in particular the M 3 tend to be large.The P4 and MI from Grytsiv are within (lowers) or aboye (upper teeth) of the metrical ranges of P. hysudricus, while the M3 are in the lower ranges.Not only the size differs, but also the proportions.
The MN 11•13 Propotamochoerus from Europe was initially placed in P. palaeochoerus, but is now recognized to be different and is believed to have affinities with P. hyotherioides (Fortelius et al., 1996) or P. hysudricus (De Bonis & Bouvrain, 1996).It replaced P. palaeochoerus at the MN 9-10 transition or early in MN 10.The genus is rare in MN 10, which explains this incertainty.A juvenile skull and mandible are known from Samos (<<Postpotamochoerus» of Thenius, 1950), a deformed skull as well as a skull fragment and other specimens from Maramena (K.palaeochoerus of Hellmund, 1995), a mandible from Ravin des Zouaves (Propotamochoerus cf.hysudricus of De Bonis & Bouvrain, 1996) and many less complete specimens from Baccinello V3 (NMB).This form has a size that is close to that of P. palaeochoerus, but it differs in the proportions of the cheek teeth (figs.1-2), in having small 1 1 with a higher crown and more elongate 12-3 (fig.4), in having the parietal ridges wider apart, and in having a skull with a more or less straight dorsal profile.The M 3 may have a third lobe with a small hexaconid (De Bonis & Bouvrain, 1996;fig. 10), which is a difference with P. hysudricus.
In figures 1-4 only material from MN 11-13 is included, so that no material of dubious affinities is included.The MN 11-13 Propotamochoerus is close in size to the Grytsiv suid, but differs in tooth proportions; the P4 and MI are relatively small and the M3 are relatively large.The P4 tends to have the metaconid closer to the protoconid than in Grytsiv.
P. hyotherioides tends to have large molars, in particular the M3, and the M 3 may either have a simple third lobe or have a small hexaconid (Van der Made & Han, 1994, respectively PI. 15, fig. 4  and PI. 16, fig.6).The tooth proportions in P. hyotherioides and the Gritsiv suid differ; the former has much larger M 3 and the latter relatively large p 4 • The canines in P. hyotherioides are much larger than in Grytsiv and have a different section.The meta-and protoconid in the P4 tend to be closer together than in Grytsiv.
P. provincialis is the largest species of the genus.It has large third molars, and the M 3 may have a hexaconid, the canines are large and the skull profile is straight.It entered in MN 13 in Europe and became extinct after MN 15.P. hyotherioides, P. provincialis and the MN 11-13 form are morphologically very similar, though the latter is the most advanced in 1 2 elongation.The relation of these three forms with the Indian one(s) is not clear.P. provincialis differs from the Grytsiv form in size and in tooth proportions.
P. palaeochoerus apeared in Europe in MN 8 (or late MN7+8).The genus is particularly abundant in MN 9, but became rare or extinct in MN 10.The species has a concave skull profile, inflated zygomatic arcs, incisors with not very high crowns, an 1 1 with a large distal cusp, not very large or elongate 1 2 -3 , small and short cm, small Cm with a particular section, M 3 with a pentaconid in the middle and no hexaconid, P4 with a relatively well developed metaconid and proportionally small M3.The morphology of the teeth from Grytsiv, including that of the incisors, canines P 4 and M 3 coincide very well with P. palaeochoerus, much better than with the other species.The teeth are within the metrical ranges for that species and the proportions are very similar in particular the small canine, large P4 and MI and small M3.The suid fossils from Grytsiv represent P. palaeochoerus.
The latest Aragonian and Early Vallesian was a time of great suoid species diversity.Up to four or five of the following species are comonly found in the same locality: Albanohyus castellensis, Listriodon splendens, Parachleuastochoerus steinheimensis, Parachleuastochoerus huenermanni or P. crusafonti, Hippopotamodon antiquus and of course P. palaeochoerus.The easternmost records of L. splendens is in China for the Middle or early Late Aragonian, but in Turkey for the latest Aragonian, of H. antiquus it is in the early Vallesian of Turkey, of the small Parachleuastochoerus in the early Vallesian of Hungary, and of both P. steinheimensis and Albanohyus in Poland (Fortelius et al., 1996; Kubiak, 1981; Van der Made,  1996).The finds from Grytsiv represent the eastern most record of Propotamochoerus palaeochoerus.

Fig
Fig. l.-Bivariate plot of the male lower canine.Legend and provenance of data as in Figure 2.
MI and M 2 (PI.2, figs. 1 & 4) have the common suine morphology.The M 3 (PI.1, fig.9; PI. 2, figs. 1 & 4) has a third lobe consisting of a pentaconid in the middle, preceeded by a pentapreconulid and several smalI cusplets and wrinkles of the enamel to the sides (formed by the pentaendocristid and pentaectocristid).A specimen from Ravin des Zouaves has a pentaconid and hexaconid (De Bonis & Bouvrain, 1996, fig.9), wheras other MN 11-13 Propotamochoerus do not have a hexaconido Hexaconids are known in the M 3 of P. hyotherioides, but not in those of P. palaeochoerus and P. hysudricus.The C r (PI. 1, fig. 4) has a 10w crown and a rapidly narrowing rool.The p4 (PI. 1, fig.l; PI. 2, fig.2) has the paracone and metacone welI separated.The paraendoconulid and metaendoconulid are clearly present, though not big.

Table I .
-Measurements (in mm) of the associated cheek teeth of Propotamochoerus paÚleochoerus from Grytsiv

Table 2 .
-Measurements of the lsolated teeth of Propotamochoerus palaeochoerus from Grytslv

Table 3 .
-Measurements of the bones of Propotamochoerus paloeochoerus from Grytslv