Fig 1.
Geographical position of the Hammerschmiede locality (A, B) and excavation plan (C) of the channel structure HAM 5 (grey areas excavated from 2011 to 2019). Dashed line represents the channel structure. Red stars represent the specimens of Buronius manfredschmidi and grey symbols represent Danuvius individuals; stars–GPIT/MA/10000 (male holotype), diamonds–GPIT/MA/10001 (female paratype), circles–GPIT/MA/10002 (juvenile paratype), triangles–GPIT/MA/10003 (female paratype). Red encircled areas have no tachymeter measurements. Coordinates correspond to Gauss-Krüger Zone 4 grid with easting (R) and northing (H) in metres. The topographic maps have been created using the Generic Mapping Tools program [25].
Fig 2.
Buronius manfredschmidi nov. gen. et sp. photographs.
Upper panel: holotype left upper M2 (GPIT/MA/13005), A–occlusal, B–buccal, C–lingual, D–mesial, E–distal. Lower panel: paratype left lower P4 (GPIT/MA/13004), F–occlusal, G–buccal, H–lingual, I–mesial, J–distal. Scale bars equal 10 mm.
Fig 3.
Buronius manfredschmidi nov. gen. et sp. surface renderings.
Upper panel: 3D rendering of the holotype left upper M2 (GPIT/MA/13005), A–occlusal, B–buccal, C–lingual, D–mesial, E–distal. Lower panel: 3D rendering of the paratype left lower P4 (GPIT/MA/13004), F–occlusal, G–buccal, H–lingual, I–mesial, J–distal. Scale bars equal 10 mm.
Fig 4.
Buronius manfredschmidi nov. gen. et sp. paratype left patella (GPIT/MA/10007).
Anterior (A), posterior (B) and distal (C) views. Scale bar equals 10 mm.
Table 1.
Buronius manfredschmidi nov. gen. et sp., tooth and patella metrics (mm).
Fig 5.
Comparison of Buronius (left, GPIT/MA/13005) and Danuvius (right, GPIT/MA/10002-07) upper M2 occlusal morphology with the nomenclature labelled on the Buronius tooth.
Pr—protocone; Prl—protoconule; MMR—Mesial marginal ridge; Pac—paracrista; Prpac—preparacone crista; Pa—paracone; Popac—postparacone crista; BS—buccal style; Prmc–premetacone crista; Me—metacone; Pomc—postmetacone crista; DMR–Distal marginal ridge; H-Mc–hypocone-metacone crista; Hyc—hypocrista; Pohc—posthypocone crista; Hy—hypocone; Prhc—prehypocone crista; CO—crista obliqua; Poprc—postprotocone crista. Note the unusual configuration of the crista obliqua (yellow line) and postprotocone crista (orange line). In Buronius the crista obliqua meets the concave postprotocone crista distal to the protocone, in contrast to Danuvius, in which the two cristae meet at the protocone tip (For a description of GPIT/MA/10002-07 see S2 File).
Fig 6.
Enamel thickness on unworn upper molars.
Distal virtual section through the tips of metacone and hypocone for the left upper M2 of Buronius manfredschmidi nov. gen. et sp. (A, GPIT/MA/13005) and the left upper M2 of Danuvius guggenmosi (B, GPIT-MA-10002-07). Note the substantial difference in enamel thickness between Buronius and Danuvius. Scale bar equals 2 mm.
Table 2.
2D relative enamel thickness of the holotype molar of Buronius manfredschmidi nov. gen. et sp. and the molars of the hypodigm of Danuvius guggenmosi.
Fig 7.
A–Comparison of lower P4 (orange bars) and upper M2 (blue bars) lengths in selected catarrhines. The relationship between these two teeth in Buronius is consistent with other catarrhines. Numbers at top are percentages of premolar to molar length. Note the much lower ratio of the Buronius P4 and the smallest Danuvius M2. B–P4/M2 within individual ratios in great apes compared with the same ratio between Buronius P4 and the smallest Danuvius M2. The box plot shows the centre line (median), box limits (upper and lower quartiles), crosses (arithmetic mean), whiskers (range) and individual values (circles).
Fig 8.
The Buronius M2 (A) compared with a dP4 (B), and M2 (C) of Danuvius and a M2 of Anapithecus (D). (A–GPIT/MA/13005; B–GPIT/MA/10002-04, inverted; C–GPIT/MA/10002-07; D–RUD 90). Scale bars equal 5 mm. Mesial is to the left.
Fig 9.
Comparative analysis of the Buronius upper M2.
A-D–Box plots of length/breadth ratios, molar size and protocone and paracone angles. Buronius falls among fossil and living apes in length/breadth and among larger primitive catarrhines and siamangs in overall size. The protocone angle (see Methods) clearly distinguishes Buronius from primitive catarrhines including Pliobates. Curiously, in paracone angle living apes are distinct from both primitive catarrhines and fossil great apes including Buronius. All box plots show the centre line (median), box limits (upper and lower quartiles), crosses (arithmetic mean), whiskers (range) and individual values (circles). C—Principal component analysis based on mesiodistal length, buccolingual breadth, ROPA, protocone and paracone angles in Buronius and dryopithecins. Hispanopithecus (green dots) and Rudapithecus (blue crosses) are mostly distinguished, with a small area of overlap. Buronius is isolated from these larger samples. It is also quite distinct from Anoiapithecus (red squares), Pierolapithecus, (brown inverted triangle), Dryopithecus (black circle), and the dryopithecin indet molars from Melchingen (magenta triangle). With larger samples from Buronius there may be less of a distinction from Danuvius. PC 1 is most strongly influenced by protocone angle and PC 2 by ROPA and paracone angle.
Fig 10.
Relative Occlusal Polygone Area (ROPA).
The ratio of M2s mesiodistal/buccolingual dimensions (X axis) relative to ROPA (see Methods section and S1 Fig). Primitive catarrhines (including Pliobates) separate well from extant hominoids, with many fossil great apes falling between the two groups. Buronius falls in the overlap of the hylobatid and Pan polygons.
Table 3.
2D relative enamel thickness (RET) in Buronius and fossil and extant hominoids.
Fig 11.
Size-adjusted morphometrics of the patella of extant and fossil catarrhines.
GM–geometric mean, ML–mediolateral breath, PD–proximodistal length, AP–anteroposterior thickness. Measurements of fossil stem-hominoids and Epipliopithecus are from [37, 38]. Note that the patella morphospace separates the families Cercopithecidae, Hylobatidae and Hominidae. Stem-hominoids (Ekembo, Equatorius, Nacholapithecus) overlap with hominids in the morphospace direction of hylobatids, e.g. they tend to be more elongate and thinner than most hominids.
Fig 12.
A–Body mass data for extant hominoids, Buronius, Danuvius and Rudapithecus from regressions of M2 size [42] and observed body masses (open boxes [43, 44]. Note the close correspondence in hylobatids of values from molar size and observed ranges, in contrast to Pan, in which dentally derived estimates of body mass significantly underestimate observed body mass (arrow). The same pattern characterizes Danuvius body mass estimates from dental vs postcranial dimensions [5] and Grabowski pers. comm. B–Patellar mediolateral breadth of living catarrhines and selected fossil hominoids (fossil data from [36–38]). Ekembo heseloni specimens are from KPS at Rusinga. Larger patella from Rusinga, tentatively attributed to Ekembo nyanzae (not shown here) fall among Danuvius and Rudapithecus. Whatever the actual body mass of Danuvius was, it was much larger than Buronius, as are all known fossil and extant hominids.
Table 4.
Relative enamel thickness in extant hominoid upper second M2 and their thickness categories and dietary affinities.