FIGURE 1. Map of Australia showing the location of Miocene wombat fossil sites.

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FIGURE 2. An animation of type specimen QM F23774, reduced for web viewing, based on CT data. The specimen was scanned at the Natural History Museum, London using a Metris X-Tek HMX ST 225 system. Volumes were constructed using CT PRO (Metris X-Tek, UK) and visualised using VG Studio Max 2.0 (Volume Graphics, Heidelberg, Germany). Click on image to run animation.

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FIGURE 3. Left maxillary fragment of Nimbavombatus boodjamullensis from Boid Site East (QM F23774). Left panel (photographs) of 1, occlusal (ventral) view of tooth row and 2, buccal (lateral) view. Scale bar represents 10 mm. Right panel (line drawings) of 3, occlusal (ventral) view and 4, buccal (lateral) view. Grey shading represents enamel.

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FIGURE 4. Left maxillary fragment of Nimbavombatus boodjamullensis from Creaser’s Ramparts Site (QM F23725). Photographs of 1, occlusal (ventral) view, 2, buccal (lateral) view and 3, lingual (medial) view. Scale bar represents 10 mm. 4, Line drawing of occlusal (ventral) view. Grey shading represents enamel. Asterisk marks presence of distinctive wear facet on trailing edge enamel (see text for details).

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FIGURE 5. Isolated molars of Nimbavombatus boodjamullensis from Creaser’s Ramparts. 1, Right M1 (QM F30339). 2, Left M1 (QM F51404). 3, Left Mx (probably M2 or M3) (QM F23773). From left to right views are: buccal, lingual, anterior, posterior, stereo of occlusal surface and line drawing of occlusal surface. Scale bar for photographs represents 10 mm. Grey shading on line drawings represents enamel. L indicates lingual side, B indicates buccal side.

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FIGURE 6. Lingual view of lower molars to show presence of enamel tracts (indicated by asterisks). 1,Nimbavombatus boodjamullensis. 2,Rhizophascolonus crowcrofti. 3, Warendja encorensis.

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FIGURE 7.1, Strict consensus tree for parsimony analysis including Marada arcanum. 2, Bootstrap support for single most parsimonious tree from analysis excluding Marada arcanum (see text for details). Vombatidae indicated in purple.

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FIGURE 8.Jaw movement during the power stroke in Nimbavombatus boodjamullensis. 1, Evidence of jaw movement on the surface of the cheek teeth. 2, Movement of the lower jaw during Phase I (left) and Phase II (right) of the power stroke.

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