FIGURE 1. Discovery location and stratigraphic position of Alierasaurus ronchii in the frame of the Permian and Triassic succession of Nurra (NW Sardinia, Italy).

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FIGURE 2. New recovered vertebral material of Alierasaurus ronchii in lateral (1, 2, 5-8, 9, 10, 15, 16, 21, 22, 27, 28), anterior and posterior (3, 4, 11, 12, 17, 18, 23, 24, 29, 30), dorsal (13, 19, 25, 31), and ventral (14, 20 26) views. NS151/10 (1-4); NS151/12 (5-6); NS151/11 (7-8); NS151/7 (9-14); NS151/8 (15-20); NS151/9 (21-26); NS151/33 (27-31). Scale bar equal to 5 cm.

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FIGURE 3. New prepared and recovered pre- and postzygapophyses of Alierasaurus ronchii in lateral (1, 4, 5, 6, 9, 10, 13, 14, 17, 18, 20), medial (2, 7), posterior (11, 15, 19, 21), dorsal (3, 8, 12) and ventral (16) views. NS151/16a-b (1-3); NS151/17 (4-5); NS151/30 (6-8); NS151/15 (9-12); NS151/16 (13-16); NS151/19 (17-19); NS151/29 (20-21). Scale bar equal to 5 cm.

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FIGURE 4. Neural spines and proximal portions of haemal arches of Alierasaurus ronchii in lateral (1, 2, 7, 11, 12, 15, 16), dorsal (5, 9, 13, 17), ventral (6, 14), anterior/posterior (3, 4, 8, 10) views. NS151/74 (1-5); NS151/48 (6-10); NS151/59 (11-14); NS151/72 (15-17). Scale bar equal to 5 cm.

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FIGURE 5. Fragmentary recovered ribs of Alierasaurus ronchii in anterior (1, 3, 5, 7, 9) and posterior (2, 4, 6, 8, 10) views. NS151/39 (1-2); NS151/40 (3-4); NS151/42 (5-6); NS151/54 (7-8); NS151/55 (9-10). Scale bar equal to 5 cm.

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FIGURE 6. Mostly complete dorsal rib NS151/75 of Alierasaurus ronchii. Anterior view (1); posterior view (2). Scale bar equal to 5 cm.

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FIGURE 7. Largest dorsal rib found to date for Alierasaurus ronchii (NS151/76). Anterior view (1); posterior view (2). Scale bar equal to 5 cm.

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FIGURE 8. Photogrammetric models of the dorsal rib of Alierasaurus ronchii (NS151/76) lying in anterior view in its original position. Meshed models in greyscale (1, 3, 5); Realistic model with textures provided by the original pictures (2, 4, 6).

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FIGURE 9. Topology obtained including Alierasaurus in a new cladistics analysis of Caseidae. Obtained cladogram showing the Bremer support (1); Result of the bootstrap analysis (2); Result of the jackknife analysis (3). Caseasauria reported in blue.

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FIGURE 10. Cladograms obtained by including the basal caseid Eocasea martini (in green) in the cladistic analysis. Strict reduced consensus of three equally parsimonious trees with basal Caseasauria (in blue) not resolved (1); E. martini falling more basal then Eothyris could be external to Caseidae (2); E. martini as sister taxon of Eothyris, thus representing an eothyridid (3); E. martini represents the most basal caseid as suggested by Reisz and Fröbisch (2014) (4).

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FIGURE 11. In vivo reconstruction of Alierasaurus ronchii by the Italian artist Emiliano Troco (oil on canvas). The reconstruction has been obtained taking as reference for comparison the mounted skeletons of Cotylorhynchus romeri OMNH 655, OMNH 1673 and the cast on slab MSNM V7161.

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