The remains of a large cercopithecid from the Lower Pleistocene locality of Karnezeika (southern Greece)

ABSTRACT The Lower Pleistocene Karnezeika locality, lies in the Peloponnese, southern Greece, and its fauna corresponds to the Middle Villafranchian biochronological unit (MN17). The recovered mammal assemblage includes, among others, a few remains of a large Cercopithecid. Herein, we describe this material, including an upper second molar, a partially preserved proximal radius and, possibly, an upper first incisor. The teeth show advanced stages of wear but retain their typical papionin characters, such as a strong lingual cleft and four bilophodont cusps in the molar. The general morphology and wear pattern of the teeth rules out the possibility that the remains belong to the genus Theropithecus, while the general size of the corresponding material excludes the possibility of a Macaca representative as well. On the contrary, the studied material better fits the size range of Paradolichopithecus. Even though this genus is likely represented in the Villafranchian of Europe by a single species, Par. arvernensis, the scarcity of the studied material imposes reservations and thus the Karnezeika papionin is referred at the moment to cf. Paradolichopithecus sp. As in the rest of Europe, the Paradolichopithecus record is rare in Greece, having been found in only two localities, Vatera and Dafnero. Despite its scarcity, the new material from Karnezeika indicates a wide distribution of this important taxon in the Greek peninsula.


Introduction
Karnezeika in eastern Peloponnese, southern Greece, is a new Lower Pleistocene, fissure-filling locality yielding a mammal fauna that corresponds to the Middle Villafranchian biochronological unit (MN17) (Sianis et al. 2022).The fauna consists mainly of bovids, including Gazella bouvrainae Kostopoulos & Athanassiou 1997, Gazellospira torticornis (Aymard 1854), Gallogoral meneghinii (Rütimeyer 1878) and Caprini gen.et sp.indet (Sianis et al. 2022), but also other artiodactyl, perissodactyl and carnivoran taxa.Among the finds, there were also rare remains of a large cercopithecid.The Cercopithecidae is a diverse family of Old-World monkeys (Catarrhini) with a former wide distribution across Africa, Asia and Europe.Taxonomically, it is divided in two subfamilies, Cercopithecinae and Colobinae, both of which are present in the fossil record of Europe (Eronen & Rook 2004), even though it is rather rare with respect to other families.In Europe, the cercopithecids appear in the Late Miocene (MN11) with the colobine Mesopithecus Wagner 1839 and disappear in the Late Pleistocene.During the Pliocene and the Pleistocene, the family showed an increased taxonomic diversification in Europe, represented by the genera Macaca de la Lacépède 1799, Dolichopithecus Depéret 1889, Theropithecus Geoffroy Saint-Hilaire 1843 and Paradolichopithecus Necrasov et al. 1961 (Szalay & Delson 1979;Frost 2017).
In the Greek cercopithecid fossil record, the colobine monkey Mesopithecus is the most frequent, known from several Upper Miocene localities of the central and northern parts of continental Grece (Koufos 2009), such as Pikermi near Athens (with Mesopithecus pentelicus Wagner 1839) and Axios Valley near Thessaloniki (with Mesopithecus delsoni de Bonis et al. 1990and Mesopithecus monspessulanus Gervais 1848-1852).In addition, another colobine monkey, Dolichopithecus, is known from the Lower Pliocene locality Megalo Embolo near Thessaloniki (Koufos et al. 1991) and from a few isolated dental specimens found in the Ptolemais Basin (Doukas & de Bruijn 2002).Spassov & Geraads (2007) included the Megalo Embolo remains to a new species, Dolichopithecus balcanicus Spassov & Geraads 2007.However, this opinion was not followed by Koufos (2009Koufos ( , 2022)), who continued to refer the Megalo Embolo sample to Dolichopithecuruscinensis Depéret 1889.As far as the Cercopithecinae are concerned, the first finds include some isolated dental remains from the locality of Tourkovounia near Athens, which were ascribed by Symeonidis & Zapfe (1977) to Macaca florentina (Cocchi 1872).Very recently, new Macaca remains were unearthed from the locality of Marathousa-1 in the Megalopolis Basin, ascribed by Konidaris et al. (2022) (Depéret 1928).For a comprehensive and up-to-date review of the Greek fossil record of Cercopithecidae, see Koufos (2022).
The purpose of this article is to describe and provide possible taxonomic information for this new cercopithecid material.Moreover, the presence of a large cercopithecid provides additional information expanding our knowledge about the taxon's distribution and the understanding about the locality's palaeoenvironment.

Materials and methods
Details about the locality of Karnezeika and its geological and stratigraphic setting can be found in Kokotini et al. (2019) and Sianis et al. (2022).The studied cercopithecid material consists of possibly an upper incisor, an isolated upper second molar and the proximal part of a right radius.The dental specimens are curated in the Palaeontological Collection of the University of Patras (PCUP), while the radius is curated in the Athens Museum of Palaeontology and Geology (AMPG).
The dental terminology largely follows Swindler (2002).Linear measurements were taken with digital calipers at two decimals precision.All measurements are given in mm.Scatter plots were created with the use of LibreOffice Calc for Windows.Remark: traditionally, the authorship of D. arvernensis was attributed to Depéret (1929) where the species was fully described.However, recently, it has been shown (Delson E. pers. comm.) that the first (i.e.original) announcement of this taxon was actually provided a year earlier by Depéret (1928) himself.In this latter article, Depéret names his new species and provides a short but meaningful description of very basic features, that could satisfy the terms of name availability under Article 12 of the International Code of Zoological Nomenclature.Material: one upper incisor (PCUP KZ1400); one left upper second molar M2 (PCUP KZ1852); and one proximal part of a right radius (AMPG KRZ93).

Systematic palaeontology
Description: specimen KZ1852 is a well preserved isolated left upper molar, which retains all three of its roots (Figs 1a-d).The crown is almost square shaped (maximum mesiodistal diameter of M2 × 100/maximum buccolingual diameter of M2 = 96.5)and includes four low bilophodont cusps (two buccal and two lingual) following the typical bilophodont morphology for the molars of the Old-World monkeys (Swindler 2002).The tooth is in a very advanced stage of wear (stage F of Delson 1973), exposing the dentine over the entire occlusal surface and resulting in complete merging of the wear facets.The inner profile is also lost to wear, placing the individual in IDAS 4 (late adult) or IDAS 5 (senile) (sensu Anders et al. 2011).Enamel is only visible at the margins of the tooth.Due to the advanced wear, the occlusal surface is reduced to dentine and appears much lower than the enamel margins and almost completely smooth, lacking any morphological characteristics.Nevertheless, despite this advanced stage of wear, the tips of the buccal cusps remain relatively pointed.The lingual cones are much lower than the buccal cones.On the distal and mesial walls two contact facets can be clearly seen indicating that the tooth is a first or second molar and most likely the latter due to its dimensions (Table 1).Strong bulging appears on the buccal side of the paracone, as can be also observed in modern baboons and macaques.A well-developed cleft (sensu Delson 1975) is visible on the lingual side of the tooth.A weak flaring is detectable, more evident in the lingual side, which was calculated based on Benefit (1993) and Singleton (2003) and found to be equal to 0.3.Such a low value may be due to the advanced stage of wear.
The specimen KZ1400 is a right incisor, most likely an upper one (Figs 1e-g).The tooth is ascribed to the same taxon due to similarities with primate incisors, though with some reservation, because of its unusual wear pattern.The occlusal surface is oval shaped (elongated mesiodistally) and devoid of any morphological characteristics, as it is in advanced stage of wear.Almost all of the surface consists of exposed dentine.The centre of the surface is low while the mesial and distal enamel ridges are high, creating a valley-like structure.A longitudinal, mesiodistally oriented groove is present in the mesial side of the tooth, at the border of the crown and the cervix.This groove, as well as the tooth as a whole, is characterised by the presence of microcracks due to taphonomic modification, as well as black stains, most likely due to the presence of manganese oxides (Fernández-Jalvo & Andrews 2016).Labially, the crown appears wide and relatively short.The root is robust and curves laterally towards its apex.Its cross-section is elliptical, slightly compressed mesiodistally.No basal bulge nor any lingual cingulum is observed.
The radius (AMPG KRZ93) preserves only the proximal part of the bone, broken a few centimetres distally of the welldeveloped radial tuberosity (Figs 1h, i).The neck of the radius is short and slightly inclined in relation to the radial tuberosity.The head of the radius is sub-circular with a shallow articular surface.

Discussion and conclusion
Characters shown by the upper M2 specimen KZ1852, such as the low cusps, the lingual cleft, the flaring and the wear pattern are typical of Papionini (Delson 1973;Swindler 2002;Frost & Kullmer 2008).On the contrary, Colobinae are characterised by an increased crown relief and an asymmetrical curve of the distal margin of the upper teeth (Szalay & Delson 1979).Dolichopithecus can be excluded based on its smaller dimensions and the lack of strong crown relief, commonly found in Colobinae (Szalay & Delson 1979).Among known Plio-Pleistocene Eurasian Cercopithecidae, Theropithecus can easily be ruled out on the basis of its particular dental morphology with high crowns, columnar cusps and significantly developed enamel folding, as well as the characteristic double cross wear pattern (Jablonski 1993;Frost 2014).As far as the other three wellknown genera are concerned, placing Macaca on the one side and the group Paradolichopithecus-Procynocephalus on the other, their molar morphology is quite similar but they differ significantly in terms of size, as shown in Figure 2. The Karnezeika molar specimen seems to correspond metrically to the Paradolichopithecus-Procynocephalus group, while it appears consistently larger than all compared macaques.The occlusal surface dimensions can provide a safe criterion in distinguishing between Macaca and Paradolichopithecus dental remains (Alba et al. 2018), therefore attribution to the former can also be discounted.
Hence, based on the aforementioned morphological characters which are typical of the Papionini (excluding Theropithecus), and the tooth dimensions (much larger than Macaca), the specimen KZ1852 most likely belongs to the genus Paradolichopithecus. Dental remains of Paradolichopithecus are practically indistinguishable from Procynocephalus and their phylogenetic relationships along with the possibility of synonymy is still a matter of debate (see Simons 1970;Szalay & Delson 1979;Nishimura et al. 2010Nishimura et al. , 2014;;Kostopoulos et al. 2018).Nevertheless, there is a consensus that the latter is an East Asian form.Moreover, in Greece the presence of Par.arvernensis has been documented already in two localities: Vatera (de Vos et al. 2002;van der Geer & Sondaar 2002;Lyras & van der Geer 2007); and Dafnero (Kostopoulos et al. 2018).
The incisor KZ1400 is quite problematic since it shows an unusual wear pattern.If its identification as a cercopithecid upper incisor is valid, then it is very likely that it belongs to the same individual as the molar KZ1852, based on the similar degree of wear and the overall preservation.However, the wear   Whatever the case, the similarities with Paradolichopithecus cannot be dismissed based on the studied molar and radius; on the other hand, the two isolated dental elements and the partially preserved radius cannot be considered as conclusive and a comparison at the species level is not reliable at the moment.Therefore, due to this scarcity of material and for propriety reasons, it is considered best to ascribe the Karnezeika large-sized primate to cf.Paradolichopithecus sp.
The ecological profile of Par.arvernensis is yet poorly understood.However, postcranial evidence indicates a large-sized terrestrial (cursorial) monkey supposedly (see van der Geer & Sondaar 2002;Sondaar et al. 2006), while dental microwear analyses suggest a mixed/opportunistic and more abrasive diet with limited grass intake/consumption (see Williams & Holmes 2011;Plastiras 2021).This fits well with the Karnezeika palaeoenvironment of restricted open landscapes between rocky terrain (Sianis et al. 2022), which further implies the capability of this large cercopithecid to occupy and exploit various habitats.
Biochronologically, the oldest Paradolichopithecus occurrence dates to around 3.2 Ma (Eronen & Rook 2004) make some remarks concerning the similarity between the bovid mammal assemblage from the locality of Karnezeika and that of the well-known locality of Dafnero in north-western Greece (Koufos et al. 1991;Kostopoulos et al. 2019 and references therein).This may mean a similar age, possibly around 2.3 Ma (Benammi et al. 2020).Further biochronologic data that may become available in the future, will certainly result in a more reliable age estimation for the locality.
Paradolichopithecus remains a rare find in Greece (Koufos 2022) and in Europe as well, with only a few specimens referred to this genus.More specifically, in the Balkan area, apart from the Greek sites mentioned above (Vatera and Dafnero), the genus is also known from two Romanian localities: Valea Graunceanului (Necrasov et al. 1961;Terhune et al. 2020); and Malushteni (Delson 1973).Similar dental finds with the ones described herein, were recently described in the same manner from the locality of Ridjake in Serbia (Radovic ́et al. 2019).Nevertheless, the few new finds described herein from Karnezeika indicate the possible presence of this important cercopithecid taxon in Peloponnesus, widening further the distribution of Paradolichopithecus in Greece.

Acknowledgements
Some data for this work were acquired from PRIMO, the NYCEP PRImate Morphology Online database (http://primo.nycep.org).Therefore, we thank Dr Eric Delson and his colleagues for allowing access to these data.Also, we thank the quarrying company Marmyk and its owner Thanasis Iliopoulos, firstly for extracting the fossiliferous block from the quarry and keeping it safely in the quarry facilities for years and secondly for providing their equipment to lift and carry the fossil-bearing blocks.

Financial support
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Conflicts of interest
None.
pattern does not correspond to the usual type found in Papionini and cercopithecine incisors, in which the labial surface appears significantly inclined, uniformly worn and the lingual side being more triangularly shaped(Shellis & Hiiemae 1986;Koufos & de Bonis 2017), and thus it could belong to a different mammal.The articular surface of the proximal end of the radius exhibits a quite rounded shape (maximum head diameter of the radius (RaDmax) × 100/minimum head diameter of the radius (RaDmin) = 110.15),which is similar to that of Par.arvernensis from Vatera (RaDmax × 100/RaDmin = 111.28).Macaca sylvanus florentina is characterised by smaller dimensions and exhibits an even more rounded articular surface of the proximal end of the radius (RaDmax × 100/RaDmin = 105.88seeFigures4 (c, d) inAlba et al. 2011).The studied radius from Karnezeika also differs from that of the modern baboon Papio hamadryas and the mandrill Papio sphinx as well.The two latter taxa have radii with an elliptical articular surface (seevan der Geer & Sondaar 2002).
to Macaca sylvanus cf.pliocena Owen 1846, as well as from the nearby locality of Kyparissia (Macaca sylvanus Linnaeus 1758; Konidaris et al.

Table 1 .
Measurements of the teeth and radius of cf.Paradolichopithecus sp. from Karnezeika.