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Fig. 9 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 9. Araucarian wood Agathoxylon mendezii sp. nov. (MPMPB15596), Estancia El Álamo, Santa Cruz Province, Argentina, Berriasian–Valanginian. Details of radial sections under SEM. A. Tracheid with slightly flattened pits (arrow). B. Tracheid showing contiguous pits with circular inner aperture. C–E. Araucarioid crossfield pits. C. General aspect. D. Contiguous alternate bordered pits placed in four vertical rows. Note circular pits in outline and circular inner aperture. E. Detail of inner apertures infilled with Si cement in elliptical form (arrow). Scale bars: A, B, E, 25 µm; C, 100 µm; D, 5 µm.

Fig. 4 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 4. XRD and SEM/EDS mineralogical and chemical analysis of Agathoxylon mendezii sp. nov. (MPMPB15596), Estancia El Álamo, Santa Cruz Province, Argentina, Berriasian–Valanginian. A. XRD pattern of the bulk sample showing quartz composition of the trunk. B. XRD pattern of the clay fraction showing no presence of clay minerals in the trunk. C, D. SEM of crossfield pits and tracheids in radial section. Note that quadrangular and rectangular areas correspond to the spot analysis shown in E–I. E–I. EDS patterns of xylem elements. E. Parenchyma ray cell wall. F. Inner aperture in crossfield pits. G, H. Tracheids cell walls. I. Tracheid pit cavity. All the EDS patterns are showing Si and O components.

Fig. 8 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 8. Araucarian wood Agathoxylon mendezii sp. nov. (MPMPB15596), Estancia El Álamo, Santa Cruz Province, Argentina, Berriasian–Valanginian. Radial sections observed under SEM. A. General aspect showing ray cells (arrow), crossfields pits (circle), axial tracheids (arrowhead). B. Detail of tracheids with uniseriate, and contiguous pits, arrow shows transition from biseriate to uniseriate pit rows. C. Detail of tracheids with biseriate, contiguous, and alternate to subopposite pits. Scale bars: A, B, 200 µm; C, 100 µm.

Fig. 3 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 3. Trunk location in the tectostratigraphic framework of the initial infilling of the AustralMagallanes Basin, from the rift stage to the beginning of the foreland stage (modified from Poiré et al. 2017). Not to scale.

Fig. 2 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 2. Outcrops of the Springhill Formation in the Estancia El Álamo locality. A. Panoramic view of the Springhill Formation outcrop overlying the El Quemado Complex. B. Polymictic conglomerate beds with a sandstone bed intercalation, Springhill Formation. C. Detail of the polymictic conglomerate with siliceous (S) and volcanic (V) clasts. D. Pyroclastic (P) and siliceous (S) clasts in the conglomerate.

Fig. 7 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 7. Araucarian wood Agathoxylon mendezii sp. nov. (MPMPB15596), Estancia El Álamo, Santa Cruz Province, Argentina, Berriasian–Valanginian. Transverse sections observed under LM. A. General aspect showing numerous, at least five frost rings (brackets). B, C. Detail of frost rings. B. Two frost rings. Note normal and rectilinear trajectory of rays (arrows) alternate with more sinuous and distended rays (arrowheads). C. Detail of frost ring cell layers, from inside to outside. Note normal tracheids that gradually grade into irregular shaped tracheids (bar) followed by a dark layer of collapsed dead cells (arrow) followed by a layer of distorted axial tracheids difficult to recognise individually. Also note dark contents in lumen cells. Scale bars: A, 3 mm; B, 1.5 mm; C, 150 µm.

Fig. 6 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 6. Araucarian wood Agathoxylon mendezii sp. nov. (MPMPB15596), Estancia El Álamo, Santa Cruz Province, Argentina, Berriasian–Valanginian. Wood sections observed under LM. A–C. Transverse view. A. Slightly marked growth ring (arrows). B. Detail of growth ring, arrow shows layers of rectangularflattened latewood tracheids. C. Detail of earlywood tracheids and rectilinear trajectory of rays (arrow). D–G. Longitudinal tangential view. D. General aspect, arrows indicate partially biseriate rays. E–G. Details of biseriate rays (arrows), arrowhead shows resin plugs. Scale bars: A, 500 µm; B, C, 150 µm; D–G, 100 µm.

Fig. 10 in Recurrent volcanic activity recorded in araucarian wood from the Lower Cretaceous Springhill Formation, Patagonia, Argentina: Palaeoenvironmental interpretations

Fig. 10. Hypothetical scenario in the Estancia El Álamo locality (Santa Cruz Province, Argentina, Berriasian–Valanginian) following volcanic disturbances. A. Preeruption stage. Seedlings, juvenile, and mature trees of Agathoxylon mendezii sp. nov. growing in a warm almost subtropical palaeoenvironment. Note volcanoes in the distance. Photo shows wood with slightly growth ring. B. Initial eruption stage. Volcanoes begin to eject silicate dust and sulfur compounds into the stratosphere. C. Climax eruption stage. Aerosol layer thickness is markedly increased producing the decrease of the surface air temperature below subzero values. Photo shows wood damaged by frost. D. Posteruption stage. Volcanoes activity begins to cease and temperature begins to rise to original values.

Fig. 6 in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 6. Comparison of sections of the wing phalanx of rhamphorhynchinae pterosaurs. A. Nesodactylus hesperius Colbert, 1969 (modified from Colbert 1969). B. Rhamphorhynchus muensteri Goldfuss, 1831 (modified from Colbert 1969). C. Ramphorhynchinae gen. and sp. indet. MUHCAL.20165, Cerritos Bayos, west Calama, Chile; Cerro Campamento Formation, middle Oxfordian. C1 and C2, cross sections of two portions of the wing phalanx. A and B, not to scale.

Fig. 2 in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 2. Rhamphorhynchinae gen. et sp. indet. (MUHNCAL.20165) from Cerritos Bayos, west Calama, Chile; Cerro Campamento Formation, middle Oxfordian. Vertebrae of indeterminate position (A1) and schematic representation (A2).

Fig. 5 in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 5. Rhamphorhynchinae gen. et sp. indet. (MUHNCAL.20165) from Cerritos Bayos, west Calama, Chile; Cerro Campamento Formation, middle Oxfordian. Fragments of a wing phalanx in dorsal (A1) and posterior (A2) views.

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Fig. 3 in First record of chimaeroid fish Ischyodus from the Upper Jurassic of southwestern Gondwana

Fig. 3. Chimaeroid fishes from Mina Del Fierro, Andes Cordillera, Región del Maule, Chile; Baños del Flaco Formation, Tithonian (Upper Jurassic). A. Ischyodus townsendi (Buckland, 1835) (MHNC.35.444); two articulated mandibular plates in basal view. B. Ischyodus sp. (MHNC.35.445); ventral view of the bony contour of a right palatine attached to the matrix, preserving the occlusal surface of the tritors. Abbreviations: ait, anterior inner tritor; aot, anterior outer tritor; bk, beak; lm, left mandibular; mt, median tritor; out, outer tritor; pit, posterior inner tritor; plm, prominence of the labial margin; pot, posterior outer tritor; r, ridges; rm, right mandibular; syt, symphyseal tritor. Photographs (A1, B1), schematic illustrations (A2, B2).

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Fig. 4 in First record of chimaeroid fish Ischyodus from the Upper Jurassic of southwestern Gondwana

Fig. 4. Comparison of mandibular plates of Tithonian species within Ischyodus Egerton, 1843. All in occlusal view. A. Ischyodus quendstedti, MJSN SCR010-1000), Tithonian of Switzerland; right mandibular, mirrored for comparison (modified from Leuzinger et al. 2017). B. Ischyodus townsendi MHNC.35.444), Tithonian of central Chile; outline of the left mandibular (only visible in basal view) is overlapped in dashed lines for a better understanding of the complete plate outline. C. Ischyodus dutertrei (holotype, specimen number 3402, Musée Boulogne-sur-le-mer, France), Kimmeridgian– Tithonian of France (modified from Sauvage 1896). D. Ischyodus townsendi (holotype, BMNH P474; currently NHMUK 010039966 PV), Tithonian of England (modified from Natural History Museum, London, Data Portal, data.nhm.ac.uk, https://doi.org/10.5519/0002965). Abbreviations: act, accessory tritor; aot, anterior outer tritor; mt, median tritor; pot, posterior outer tritor; syt, symphyseal tritor.

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Fig. 2 in First record of chimaeroid fish Ischyodus from the Upper Jurassic of southwestern Gondwana

Fig. 2. Stratigraphic section of the levels were the studied material was recovered. Modified from Quinzio and Varela (2015).

Fig. 1. A in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 1. A. Geographic location of the study area indicating the location of Cerro Campamento, the site where the discovery was made. B. General scheme of the stratigraphic section which includes the Cerro Campamento Formation, indicating horizons with vertebrate remains and the pterosaur materials here studied. Kim., Kimmeridgian. Modified from Biese (1961).

Fig. 3 in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 3. Rhamphorhynchinae gen. et sp. indet. (MUHNCAL.20165) from Cerritos Bayos, west Calama, Chile; Cerro Campamento Formation, middle Oxfordian. Left humerus in dorsal (A1, A5), posterodorsal (A2, A6), posterior (A3, A7), and ventral (A4, A8) views, photographs (A1–A4) and explanatory drawings (A5–A8). Zone of Subvinialesphinctes prophetae and Euaspidoceras centrum. However, we cannot assure that this ratio is natusp., middle Oxfordian. ral since the vertebral centrum is not complete. Only one in- Descriptions.—Vertebra: Among the remains there is a sin- complete transverse process is preserved (preserved length gle incomplete vertebra (Fig. 2). This is visible in articular of ~4.5 mm). This arises from the top of the neural arch and view and it is very eroded; it is difficult to stablish whether has a dorsolateral orientation. Proximally, the height of the it is exposed in anterior, posterior, or in an approximately transverse process represents almost half of the centrum oblique view. The neural spine is tall (preserved height is height, narrowing distally. Due to its incompleteness, its 6.3 mm), as described for Rhamphorhynchinae (Witton extension cannot be established. The neural canal is broad, 2013: 129) especially in the cervical vertebrae, although rel- being wider than high and representing ca. three fifths of atively tall and rectancular neural spines are also seen in the the preserved centrum width. The poor preservation of the anterior dorsal vertebrae of Rhamphorhynchus (see Bonde material makes it difficult to assess the exact shape and and Christiansen 2003: fig. 5). The neural spine is laterally proportions of the neural canal, although it appears to have compressed and slightly higher than the preserved vertebral a dorsoventrally compressed oval shape. The centrum is

Fig. 7 in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 7. Simplified map of the world during the Oxfordian. The dashed line represents the hypothetical route that would have allowed the dispersal of marine vertebrates and invertebrates between Tethys and South America during the Late Jurassic (Caribbean corridor). The finds of Oxfordian rhamphorhinchids: MUHNCAL.20165 (Rhamphorhynchinae gen. et sp. indet.), Cerro Campamento Formation, Chile (circle); Cacibupteryx caribensis (Gasparini et al. 2004) and Nesodactylus hesperius (Colbert et al. 1969), Jagua Formation, Cuba (square); Rhamphorhynchinae gen. et sp. indet. (Lydekker 1890, O'Sullivan 2018), Oxford Clay Formation, UK (star); Qinglongopterus guoi (Lü et al. 2012), Tiaojishan Formation, China (triangle). Modified map from Scotese (2014).

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Fig. 2 in The fossil record of camelids demonstrates a late divergence between Bactrian camel and dromedary

Fig. 2. Time-calibrated equiparsimonious trees. At each node, the probability density computed by diversification is shown (in red, all displaying a left skew). The age of each fossil record (in million years) is shown as a brown bar along each branch, which extends from the oldest to the youngest plausible age for each record. Darker shades represent overlapping possible age ranges, whereas brown dots represent very well-dated fossils. Extant taxa are in bold. A monophyletic Camelus is diagnosed by the loss of p3 and a smaller P3. The Paracamelus clade is diagnosed by a long muzzle. Camelus grattardi lacks derived characters of other representatives of the Camelus clade, the paraglenoid process, a shallower infra-orbital shelf, an oblique ascending ramus of the mandible, a thickened corpus, a broader P4 relative, and long ligament scars on the phalanges. The position of the poorly studied Camelus knoblochi relative to extant forms rests only on the morphology of the choanae.

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Fig. 1 in The fossil record of camelids demonstrates a late divergence between Bactrian camel and dromedary

Fig. 1. Probability density histograms of speciation (cladogenesis), extinction and fossilization rates for the three equiparsimonious trees. All rates are in events per lineage and per million years. The height of each box of the plots is proportional to the posterior probability for the corresponding rate to be in the interval delineating its base.