Fig 1.
Geological and geographical setting of La Retama fossil site within the Loranca Basin in the Iberian Peninsula.
Map illustration by IMS, modified from [41].
Fig 2.
Cranial remains of Xenokeryx amidalae gen. et sp. nov. from La Retama.
A, MNCN-74448 (holotype), occipital appendage in anterior view; B, MNCN-74448 (holotype), occipital appendage in lateral view; C, MNCN-74448 (holotype), occipital appendage in posterior view; D, MNCN-74449, right ossicone and supra-orbital region of a skull in latero-distal view; E, MNCN-74449, right ossicone and supra-orbital region of the skull in medial view; F, MNCN-74446, left juvenile ossicone and supra-orbital region of the skull in lateral view; G, MNCN-74446, left juvenile ossicone and supra-orbital region of the skull in medial view; H, MNCN-74447, left juvenile ossicone in apical view, showing its transversal section; I, MNCN-74449, detail of the ossicone-frontal bone contact showing the suture line (not to scale). Abbreviations: Bp, bumps; Nf, nuchal fossa; Ow, ossicone ‘wing’; Sl, suture line between ossicone and frontal bone.
Fig 3.
Upper dentition remains of Xenokeryx amidalae gen. et. sp. nov. from La Retama.
A, MNCN-74495, left maxillar with DP2-M1 in buccal view; B, MNCN-74495, left maxillar with DP2-M1 in occlusal view; C, MNCN-74452, right M3 in lingual view; D, MNCN-74452, right M3 in buccal view; E, MNCN-74452, right M3 in occlusal view; F, MNCN-74450, left P4-M1 in lingual view; G, MNCN-74450, left P4-M1 in buccal view; H, MNCN-74450, left P4-M1 in occlusal view; I, MNCN-74451, right P3 in lingual view; J, MNCN-74451, right P3 in buccal view; K, MNCN-74451, right P3 in occlusal view; L, MNCN-74453, right P2 in buccal view; M, MNCN-74453, right P2 in lingual view; N, MNCN-74453, right P2 in occlusal view.
Fig 4.
Lower dentition remains of Xenokeryx amidalae gen. et sp. nov. from La Retama.
A, MNCN-74455, right hemimandibular fragment with m2-m3 in buccal view; B, MNCN-74455, right hemimandibular fragment with m2-m3 in lingual view; C, MNCN-74455, right hemimandibular fragment with m2-m3 in occlusal view; D, MNCN-74456, left hemimandibular fragment with m1-m3 in buccal view; E, MNCN-74456, left hemimandibular fragment with m1-m3 in lingual view; F, MNCN-74456, left hemimandibular fragment with m1-m3 in occlusal view; G, MNCN-74458, right hemimandible with p3-m3 in buccal view; H, MNCN-74458, right hemimandible with p3-m3 in lingual view; I, MNCN-74458, right hemimandible with p3-m3 in occlusal view; J, MNCN-74457, right m3 in buccal view; K, MNCN-74457, right m3 in lingual view; L, MNCN-74457, right m3 in occlusal view.
Fig 5.
Fore limb remains and phalanges of Xenokeryx amidalae gen. et sp. nov. from La Retama.
A, MNCN-74460, proximal fragment of right radius in cranial view; B, MNCN-74460, proximal fragment of right radius in caudal view; C, MNCN-74459, distal fragment of right radius in cranial view; D, MNCN-74459, distal fragment of right radius in caudal view; E, MNCN-74472, proximal fragment of metacarpal III-IV in proximal view; F, MNCN-74473, proximal fragment of left radius in proximal view; G, MNCN74461, articular fragment of left scapula in lateral view; H, MNCN-74465, distal fragment of metacarpal III-IV in dorsal view; I, MNCN-74465, distal fragment of metacarpal III-IV in palmar view; J, MNCN-74486, first phalanx in external view; K, MNCN-74486, first phalanx in interdigital view; L, MNCN-74486, first phalanx in palmar/plantar view; M, MNCN-74487 in external view; N, MNCN-74487 in interdigital view; O, MNCN-74493, right pyramidal in lateral view; P, MNCN-74493, right pyramidal in medial view; Q, MNCN-74484, right semilunate in proximal view; R, MNCN-74484, right semilunate in distal view; S, MNCN-74483, left magnotrapezoid in proximal view; T, MNCN-74483, left magnotrapezoid in distal view.
Fig 6.
Hind limb remains of Xenokeryx amidalae gen. et sp. nov. from La Retama.
A, MNCN-74471, proximal fragment of left femur in cranial view; B, MNCN-74471, proximal fragment of left femur in caudal view; C, MNCN-74475, distal fragment of metatarsal III-IV in dorsal view; D, MNCN-74464, proximal fragment and diaphysis of left metatarsal III-IV in dorsal view; E, MNCN-74464, proximal fragment and diaphysis of left metatarsal III-IV in plantar view; F, MNCN-74466, distal fragment of left tibia in cranial view; G, MNCN-74466, distal fragment of left tibia in caudal view; H, MNCN-74466, distal fragment of left tibia in distal view; I, MNCN-74469, right calcaneus in medial view; J, MNCN-74469, right calcaneus in lateral view; K, MNCN-74470, right calcaneus in medial view; L, MNCN-74470, right calcaneus in lateral view; M, MNCN-74477, right navicular-cuboid in proximal view; N, MNCN-74479, left navicular-cuboid in proximal view; O, MNCN-74477, right navicular-cuboid in distal view; P, MNCN-74479, left navicular-cuboid in distal view; Q, MNCN-74480, right navicular-cuboid in plantar view; R, MNCN-74502, right ectomesocuneiform in proximal view; S, MNCN-74501, right ectomesocuneiform in proximal view; MNCN-74500, right ectomesocuneiform in proximal view; U, MNCN-74476, left astragalus in dorsal view; V, MNCN-74476, left astragalus in plantar view; X, MNCN-74482, right malleolar in medial view. Abbreviations: Cr, crest.
Fig 7.
Phylogenetic relationships among palaeomerycids.
Bootstrapped MPT of 45 steps (CI = 0,889; RI = 0,861). Bootstrap values (1000 replicates) over each node.
Table 1.
Xenokeryx and palaeomerycids, distribution of autapomorphic character states for the internal nodes and Xenokeryx.
Ambiguous synapomorphies in italics.
Fig 8.
Phylogenetic relationships of palaeomerycids within the Pecora.
Bootstrapped MPT of 205 steps (CI = 0,541; RI = 0,700). Bootstrap values (1000 replicates) over each node. Dromomerycid and palaeomerycid terminals are highlighted.
Fig 9.
Phylogenetic relationships of palaeomerycids within the Pecora.
Maximum clade credibility time-tree of major ruminant clades obtained from our ‘tip-dating’ Bayesian analysis. Uncertainty in divergence ages is shown with horizontal grey bars representing their 95% highest posterior densities (HPDs). Numbers above each branch show the posterior probability (PP) of the respective clade.
Table 2.
Palaeomerycids within the Pecora, distribution of character states for the discussed internal nodes of the MPT.
Ambiguous synapomorphies in italics.
Table 3.
Palaeomerycids within the Pecora, distribution of the reconstructed morphological character states for the discussed internal nodes of the Bayesian tree.
Ambiguous synapomorphies in italics.
Fig 10.
Life reconstruction of the head of Xenokeryx amidalae gen. et sp. nov.
Adult male based on the fossils from La Retama. Illustration by IMS.
Fig 11.
Summary scheme showing a calibrated phylogeny of palaeomerycids (based on the corresponding MPT) with special emphasis on the main morphological traits of each basal clade (Ampelomeryx-clade and Triceromeryx-clade represented by reconstructions of Ampelomeryx and Xenokeryx) including their biogeographic distribution. Illustrations by IMS.