Figure TEXT-FIG. 12.. Dentition of Promegantereon ogygia from Batalllones-1. A–B, left upper canine, B-3116, in A, buccal, and B, lingual views. C–D, left upper canine, B-566, in C, buccal, and D, lingual views. E–G, left I3, B-2490, in E, buccal, F, lingual, and G, distal views. H–J, left i3, B-1981, in H, buccal, I, lingual, and J, distal views. K–L, right lower canine, B-1007, in K, lingual, and L, buccal views. M–N, right lower canine, B-1471, in M, lingual, and N, buccal views. O–Q, right P3, BAT-1′02 D7-72, in O, occlusal, P, lingual, and Q, buccal views.
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Material. Batallones-1: 16 complete or partial skulls (BAT-1′06 F6-57, B-6051, B-3434, B-4869, B-5197, B-3848, B-7022, B-4236, B-5406, B-7021, B-4766 (1), B-4054, B-1377, B-847, B-4322 and B-4778), 16 complete or incomplete mandibles (BAT-1′01 E5-17, B-5198, B-5269, B-732, B-2376, B-4208, B-1676, B-462, B-3848, B-751, B-2270, B-134, B-5406, B-7042, B-1377, B-4322 and B-4778), 20 upper canines (B-566, B-5270 (1), B-568, B-3116, B-271, B-7022, B-4322, B-5197, B-4869, B-1377, B-847, B-3961, B-3693, B-4640, B-4418, B-1, B-241, B-4236, B-5406 and B-4778), 11 P3 (B-7022, B-7021, B-3570, B-4322, B-3848, B-5406, B-1377, B-847, B-3434, B-5197 y B-4778), 13 P4 (B-1959, B-7022, B-7021, B-3570, B-3848, B-4766 (1), B-5406, B-1377, B-847, B-4322, B-3434, B-5197 and B-4778), 17 lower canines (B-96, B-1524, B-1007, B-1471, B-1117, B-601, B-4552, B-3848, B-134, B-5406, B-7042, B-1377, B-847, B-432 (2), B-1676, B-5198 and B-4778), 14 p3 (B-7042, B-2270, B-751, B-3848, B-134, B-5406, B-1377, B-847, B-4322, B-2376, B-4208, B-462, B-1676 and B-5198), 13 p4 (B-1961, B-751, B-7042, B-3848, B-3574, B-134, B-5406, B-4322, B-2376, B-4208, B-462, B-1676 and B-5198) and 11 m1 (B-2270, B-751, B-7042, B-3848, B-134, B-2673, B-1676, B-2376, B-4208, B-462 and B-5198), 1 D3 (B-6051), and several M1 and incisors.
Cranium. The skull of Promegantereon ogygia (Text-fig. 10A–F) is similar in size to that of an extant puma (Puma concolor). The nasals are relatively narrow, sub-rectangular in shape, with rostral and caudal margins of similar width and slightly curved caudally. The rostral border of the premaxilla is slightly curved rostrally, producing a U-shaped arcade, although less procumbent than that of Pa. orientalis. There is a short diastema, approximately 12 mm long, between I3 and the upper canine. The postorbitary process of the frontal is sharp, rough, and slightly laterally projected. The lambdoidal and sagittal crests are strong and very well developed. The frontal and sagittal crests join at the level of the postorbitary process of the frontal. The infraorbitary foramen is large and placed at the level of P3. The lacrimal foramen is placed in the inner face of the rostral border of the orbit. There is a very robust nuchal crest. The sphenopalatine foramen is smaller than that of a pantherin; it is placed in the orbital wall of the palatine bone, close to the suture maxillo-palatine. The posterior palatine foramen is much smaller than the sphenopalatine foramen, and it is located slightly rostrally to the latter. The optic foramen and the orbital fissure are placed as in a pantherin cat, so that the optic foramen is located slightly above and rostrally to the orbital fissure. The rotundum foramen is also developed as in pantherins, being located on the dorsal border of the caudal end of the pterygoid process. The oval foramen opens on the basisphenoid bone, between the pterygoid process and the postglenoid process. The zygomatic arch is much more robust than that of a similarly sized pantherin, and higher dorso-ventrally; its dorsal border, which delimits the ventral margin of the orbit, is straight. The postorbitary process of the zygomatic is vestigial, but it is always present. A central ridge, which runs from the level of the condyloid foramen to the aperture of the Eustachian tube, is frequently apparent in the basioccipital. The condyloid foramen is clearly separated from the posterior lacerum foramen and thus there is not a common depression for both foramina. The tympanic bullae are less inflated than those of a pantherin; they are developed from the paraoccipital process to the caudal border of postglenoid process, without making contact with the latter. The caudal ectotympanic penetrates rostrally beside the medial margin of the ectotympanic. The external auditory meatus is a single opening, rostro-laterally oriented. The stylomastoid foramen and the tympano-hyal depression are very close to each other. Both are placed in a more rostral position than in pantherins, that is, at the level of the central part of the bulla. The paraoccipital process is reduced in size when compared with that of pantherins, being dorsally displaced in comparison with its position in the latter. The mastoid process is well developed and projected ventrally to the level of the ventral border of the tympanic bulla. The pterygoid process has a rostrally curved caudal border. The palate is triangular-shaped, with a nasopharyngeal fossa delimitated by the walls of the pterygoid bone. The palatine fissurae are placed close to the rostral border of palate.
Upper incisors. I1 has a laterally flattened crown, without cingulum, but with a smooth basal tuberosity on the lingual side. I2 is slightly larger and less compressed than I1; its lingual basal border has a light crest. I3 (Text-fig. 12E–G) is much larger than the other incisors; its crown is sharp and caniniform; its mesial surface is convex and smooth, whereas the distal one is concave and bears a light cingulum along its lingual border; on the buccal surface, there is a marked ridge from the base to the tip of the crown.
Upper canines. The crown of the upper canines is laterally flattened and curves backwards (Text-fig. 12A–D). There are no crenulations on its margins. Both buccal and lingual surfaces are smooth, although the mesio-lingual border bears a marked crest developed from the base to the middle of the crown.
P3. This tooth (Text-fig. 12O–Q) is placed parallel to the maxilla margin, with its mesial half slightly displaced lingually. The crown is mesio-distally lengthened, with a straight buccal border, and a marked disto-lingual protuberance, showing a marked constriction at the level of the main cusp; there is no cingulum, except on the distal border. There is no mesial cusp, whereas the distal and central cusps are strong with the latter being much higher. Just posterior to the distal cusp, there is a very much reduced distal tubercle.
P4. The upper carnassial has a strong protocone, placed between the parastyle and paracone and buccally oriented (Text-fig. 13D–E). The parastyle is well developed, and there is no trace of ectostyle. The metacone-metastyle edge is slightly shorter than the parastyle, with a marked notch separating both structures. There is no cingulum. P3 and P4 are aligned in occlusal view.
M1. This tooth (Text-fig. 13E) is very much reduced, although it has two roots; it has a bucco-lingually lengthened crown, which bears a light ridge developed from the mesio-buccal to the lingual borders.
D3. The paracone (Text-fig. 13F–G) is well developed. The parastyle is very low, and in its mesial border there is a marked and buccally displaced ectostyle. The metacone is also low and is followed by a shortened metastyle. The protocone is strong and placed at the level of the metacone, which means displaced posteriorly in relation to the P4 protocone.
Mandible. The mandibular corpus has two mental foramina, the anterior one being placed at the level of the postcanine diastema, and the posterior one, which is smaller, at the level of p3 (Text-fig. 11A–H). Nevertheless, the size of these foramina is very variable within the Batallones-1 sample and thus probably lacks taxonomic value. There may be accessory foramina, very small and placed around the mental foramina. The mandibular symphysis has a verticalized anterior border, and there is an almost straight angle between the ventral border of the symphysis and the mandibular corpus. In anterior view, the symphysis is high and rectangular-shaped; its lateral margins develop a light mental ridge, more marked in its ventral half. The masseteric fossa is deep and its anterior border reaches the level of the m1 protoconid. The coronoid process is lower than that of pantherins; its posterior margin shows a smooth backwards curvature and does not surpass the level of the anterior margin of the mandibular condyle. The angular process is postero-ventrally oriented, with a rough lateral border; its medial surface has an antero-posteriorly oriented ridge that produces a marked groove. The mandibular foramen is placed close to the ventral border, behind the level of the anterior margin of the coronoid process.
Lower incisors. i1 has a laterally flattened crown, more than that of I1 (Text-fig. 12H–J). i2 is less compressed than i1; both i1 and i2 have morphologically very simple crowns. The crown of i3 is triangular-shaped, although less sharp than that of I3; the mesial face is smooth and convex, whereas the distal one is concave and has a light tuberosity in the disto-lingual border of its base; i3 is larger than i1 and i2, but the difference in size is less than that seen between the upper incisors.
Lower canines. The crown is clearly smaller than that of the upper canine; it shows a smooth lateral compression, and it is curved backwards (Text-fig. 12K–N). The lingual face is concave and has a longitudinal ridge, whereas the buccal face is smooth and slightly convex.
p2. This tooth is very much reduced and single-rooted, but it is present in 54% of the available sample of hemimandibles. Its crown is very small, low and has an elliptical shape that is mesiodistally elongated.
p3. The crown is triangularly shaped, with a low central cuspid and a reduced distal one (Text-fig. 13A–C). There is no mesial cuspid. Behind the distal cuspid, there is a smooth posterior cingulum. In occlusal view, the mesial sharpening of the crown can be seen. This piece is not aligned with p4 and m1, its mesial part being lingually oriented.
p4. The crown is triangularly shaped, with a high central cuspid and small mesial and distal cuspids (Text-fig. 13A–C); both mesial and distal cuspids are separated from the central one by marked notches. The crown has a marked posterior cingulum around the distal cuspid. As in p3, the crown of p4 is sharpened mesially.
m1. The protoconid is higher than the paraconid, and they are separated by a marked notch (Text-fig. 13A–C). The talonid is reduced, but retains a tiny metaconid. There is no trace of a cingulum.
Discussion. With the description of the new material from Batallones-1, the separation of Promegantereon ogygia from those species included in the genus Paramachaerodus is clear. In 1913, when Pilgrim introduced the genus, the species Pr. ogygia was solely known from some fragments of mandible with lower dentition, and with no available information on its upper dentition and skull morphology. Nevertheless, because Pa. orientalis, Pa. schlosseri and Pr. ogygia shared a reduced p3, all these forms were placed by Pilgrim within the same genus and separated from the Metailurini, the other group of similarly sized sabre-toothed cats. More recently, the excavations at Batallones-1 have yielded a huge amount of new anatomical information on Pr. ogygia and show it to be more primitive than the forms from Pikermi and Maragheh and also from the Metailurini. In the process, the Batallones-1 felid has become one of the best known of the machairodontines, and a complete characterization of its dental, cranial and mandibular anatomy has finally been possible. These new data clearly indicate its separation from Paramachaerodus and the need for another genus, Promegantereon, to accommodate that separation. Text-figure 14 shows the phylogenetic relationships discussed here in the form of a cladogram, characters used in which are given in the Appendix S1.
Figure TEXT-FIG. 14.. Cladogram showing the phylogenetic relationships of the machairodontine genera Promegantereon and Paramachaerodus, and the primitive felids Pseudaelurus quadridentatus and Proailurus lemanensis. The numbers indicate which characters support each clade.
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The temporal range of Pr. ogygia in Eurasia is from MN 9 to MN 11, although in Spain this species is recorded in MN 10 (Batallones-1) and MN 11 (Crevillente-2). The holotype from Eppelsheim, a fragment of left hemimandible with lower canine, p3 and p4, is smaller than most of the homologous pieces from Batallones-1, but there is one hemimandible from this latter locality with p3-m1 (BAT-1′01 E5-17) that is even smaller than the holotype. There are also some small differences between the holotype and the Batallones-1 sample: the p3 from Eppelsheim is aligned with p4, whereas in the Spanish sample it is lingually oriented, although the whole area of the alveolus of p3 in the holotype is broken and glued and thus its orientation may require re-assessment; the p3 from the holotype seems to be less reduced in comparison with p4; the p4 in the holotype shows a much less developed posterior cingulum; and finally, the mandibular corpus is lower in the Batallones-1 specimens. Nevertheless, considering the different age of the two samples and the state of preservation of the holotype, we regard all these differences as being within the expected range of intraspecific variation, and we do not find reasons to separate the forms into different species.